Zoom lens and imaging apparatus

ABSTRACT

The zoom lens includes, as lens groups, in order from the object side, only a first lens group having a positive power, a second lens group having a negative power, a third lens group having a positive power, a fourth lens group having a negative power, and a fifth lens group having a positive power. An aperture stop is disposed between a lens surface closest to the image side in the second lens group and a lens surface closest to the object side in the fourth lens group. During zooming, at least the first lens group, the second lens group, the third lens group, and the fourth lens group move. The first lens group consists of a negative lens, a positive lens, and a positive lens in order from the object side. The zoom lens satisfies predetermined conditional expressions.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 toJapanese Patent Application No. 2018-221597, filed on Nov. 27, 2018. Theabove application is hereby expressly incorporated by reference, in itsentirety, into the present application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present disclosure relates to a zoom lens and an imaging apparatus.

2. Description of the Related Art

In the related art, as a zoom lens applicable to a digital camera or thelike, in order from the object side, a zoom lens having a five-groupconfiguration has been known. The zoom lens consists of a first lensgroup having a positive refractive power, a second lens group having anegative refractive power, a third lens group having a positiverefractive power, a fourth lens group having a negative refractivepower, and a fifth lens group having a positive refractive power. Forexample, JP2017-156426A and JP2017-053889A describe zoom lenses havingthe above-mentioned configuration.

SUMMARY OF THE INVENTION

The zoom lens having the above-mentioned configuration is mostly usedfor a so-called standard zoom lens that covers a wide-angle range to astandard range or a middle telephoto range. In recent years, there hasbeen an increase in demand for a wide angle of view at the wide-angleend and for the entire optical system to be made more compact whileensuring high optical performance. Further, even in a case where theangle of view at the wide-angle end increases, it is required to have ahigh zoom ratio in order to ensure a long focal length at the telephotoend.

However, the zoom lenses of Examples 1 and 2 described in JP2017-156426Ahave a long total optical length at the wide-angle end with respect tothe maximum image height. In the zoom lens of Example 3 described inJP2017-156426A, the first lens group has two lenses, and it cannot besaid that the angle of view at the wide-angle end is sufficiently wide,and the total optical length at the wide-angle end with respect to themaximum image height is long. In the zoom lenses of Examples 4 to 8described in JP2017-156426A, the first lens group consists of one lens,and it is difficult to correct spherical aberration and longitudinalchromatic aberration at the telephoto end. Thus, the high zoom ratio isnot ensured. Most of the zoom lenses described in JP2017-053889A eachhave a long back focal length and a long total optical length as awhole.

The present disclosure has been made in consideration of theabove-mentioned situations, and it is the object of the presentdisclosure to provide a zoom lens, which is reduced in size and hasfavorable optical performance while ensuring a wide angle of view and ahigh zoom ratio, and an imaging apparatus including the zoom lens.

According to an aspect of the present disclosure, there is provided azoom lens comprising, as lens groups, only five lens groups consistingof, in order from an object side to an image side: a first lens groupthat has a positive refractive power; a second lens group that has anegative refractive power; a third lens group that has a positiverefractive power; a fourth lens group that has a negative refractivepower; and a fifth lens group that has a positive refractive power. Anaperture stop is disposed between a lens surface closest to the imageside in the second lens group and a lens surface closest to the objectside in the fourth lens group. During zooming, by changing all distancesbetween lens groups adjacent to each other in a direction of an opticalaxis, at least the first lens group, the second lens group, the thirdlens group, and the fourth lens group move along the optical axis. Thefirst lens group consists of, in order from the object side to the imageside, a first lens having a negative refractive power, a second lenshaving a positive refractive power, and a third lens having a positiverefractive power. Assuming that a focal length of the first lens groupis f1, a focal length of the fifth lens group is f5, a focal length ofthe fourth lens group is f4, and a refractive index of the second lensat a d line is Nd2, Conditional Expressions (1), (2), and (3) aresatisfied, which are represented by

0.4<f1/f5<2  (1),

−0.7<f4/f5<−0.1  (2), and

1.6<Nd2<2  (3).

In the zoom lens of the above-mentioned aspect, assuming that a backfocal length at an air conversion distance in a state where the objectat infinity is in focus at a wide-angle end is BFw, and a sum of adistance on the optical axis from a lens surface closest to the objectside to a lens surface closest to the image side and the back focallength at the air conversion distance in the state where the object atinfinity is in focus at the wide-angle end is TLw, it is preferable tosatisfy Conditional Expression (4) represented by

0.07<BFw/TLw<0.25  (4).

In the zoom lens of the above-mentioned aspect, it is preferable thatthe entire third lens group or a part of the third lens group moves in adirection intersecting with the optical axis for image blur correction.

In the zoom lens of the above-mentioned aspect, it is preferable thatthe third lens group consists of, in order from the object side to theimage side, a third lens group front group having a positive refractivepower and a third lens group rear group having a positive refractivepower. In addition, it is preferable that only the third lens group reargroup moves in a direction intersecting with the optical axis for imageblur correction. In this configuration, it is preferable that the thirdlens group front group consists of two positive lenses and one negativelens. In this configuration, assuming that a focal length of the thirdlens group rear group is f3R, a focal length of the third lens groupfront group is f3F, a lateral magnification of the third lens group reargroup in a state where the object at infinity is in focus at a telephotoend is β3Rt, a combined lateral magnification of the fourth lens groupand the fifth lens group in the state where the object at infinity is infocus at the telephoto end is β45t, and an Abbe number of the at leastone positive lens in the third lens group rear group based on the d lineis νd3Rp, it is preferable to satisfy at least one of ConditionalExpressions (5), (6), or (7) represented by

0.1<f3R/f3F<0.9  (5),

2<(1−β3Rt)×β45t<5  (6), and

65<νd3Rp<105  (7).

In the zoom lens of the above-mentioned aspect, only the fourth lensgroup may move along the optical axis during focusing from an object atinfinity to a close-range object. In this configuration, assuming that alateral magnification of the fourth lens group in a state where theobject at infinity is in focus at a telephoto end is β4t, and a lateralmagnification of the fifth lens group in the state where the object atinfinity is in focus at the telephoto end is β5t, it is preferable tosatisfy Conditional Expression (8) represented by

−7<(1−β4t ²)×β5t ²<−2.6  (8).

In the zoom lens of the above-mentioned aspect, the fourth lens groupmay consist of one positive lens and one negative lens. In thisconfiguration, assuming that an Abbe number of the negative lens of thefourth lens group based on the d line is νd4n, and an Abbe number of thepositive lens of the fourth lens group based on the d line is νd4p, itis preferable to satisfy Conditional Expression (9) represented by

5<νd4n−νd4p<26  (9).

In the zoom lens of the above-mentioned aspect, assuming that a sum of adistance on the optical axis from a lens surface closest to the objectside to a lens surface closest to the image side and a back focal lengthat an air conversion distance in a state where an object at infinity isin focus at a wide-angle end is TLw, and a maximum image height is Y, itis preferable to satisfy Conditional Expression (10) represented by

6<TLw/|Y|<8.6  (10).

In the zoom lens of the above-mentioned aspect, assuming that a distanceon the optical axis between the fourth lens group and the fifth lensgroup in a state where an object at infinity is in focus at a telephotoend is D45t, and a distance on the optical axis between the fourth lensgroup and the fifth lens group in the state where the object at infinityis in focus at the wide-angle end is D45w, it is preferable to satisfyConditional Expression (11) represented by

2<D45t/D45w<13  (11).

In the zoom lens of the above-mentioned aspect, assuming that a backfocal length at an air conversion distance in a state where an object atinfinity is in focus at a wide-angle end is BFw, a focal length of thezoom lens in the state where the object at infinity is in focus at thewide-angle end is fw, and a maximum half angle of view in the statewhere the object at infinity is in focus at the wide-angle end is ωw, itis preferable to satisfy Conditional Expression (12) represented by

0.5<BFw/(fw×tan|ωw|)<1.6  (12).

In the zoom lens of the above-mentioned aspect, assuming that an averageof the refractive index of the second lens at the d line and arefractive index of the third lens at the d line is NdG1p, it ispreferable to satisfy Conditional Expression (13) represented by

1.63<NdG1p<1.9  (13).

In the zoom lens of the above-mentioned aspect, assuming that a focallength of the second lens group is f2, and a focal length of the thirdlens group is f3, it is preferable to satisfy Conditional Expression(14) represented by

−1.3<f2/f3<−0.4  (14).

In the zoom lens of the above-mentioned aspect, it is preferable thatthe fifth lens group consists of two positive lenses and one negativelens.

According to another aspect of the present disclosure, there is providedan imaging apparatus comprising the zoom lens of the above-mentionedaspect.

In the present specification, it should be noted that the terms“consisting of ˜” and “consists of ˜” mean that the lens may include notonly the above-mentioned elements but also lenses substantially havingno refractive powers, optical elements, which are not lenses, such as astop, a filter, and a cover glass, and mechanism parts such as a lensflange, a lens barrel, an imaging element, and a camera shakingcorrection mechanism.

In addition, the term “˜group that has a positive refractive power” inthe present specification means that the group has a positive refractivepower as a whole. Likewise, the “˜group having a negative refractivepower” means that the group has a negative refractive power as a whole.The term “a lens having a positive refractive power” and the term “apositive lens” are synonymous. The term “a lens having a negativerefractive power” and the term “negative lens” are synonymous. The “lensgroup” is not limited to a configuration using a plurality of lenses,but may consist of only one lens.

The “single lens” means one uncemented lens. However, a compositeaspheric lens (a lens that consists of a spherical lens and an asphericlayer formed to be bonded to at least one of the object side surface orthe image side surface of the spherical lens and that functions as oneaspheric lens as a whole) is not regarded as a cemented lens, but istreated as a single lens. The sign of the refractive power and thesurface shape of the lens surface of a lens including an asphericsurface are considered in terms of the paraxial region unless otherwisenoted.

In this specification, the term “focal length” used in ConditionalExpression is a paraxial focal length. The term “back focal length atthe air conversion distance” is an air conversion distance on theoptical axis from the lens surface closest to the image side to thefocal position on the image side. The total optical length is a sum of aback focal length as an air conversion distance and a distance on theoptical axis from the lens surface closest to the object side to a lenssurface closest to the image side. The values used in ConditionalExpressions are values on the d line basis. The partial dispersion ratioθgF between the g line and the F line of a certain lens is defined byθgF=(Ng−NF)/(NF−NC), where Ng, NF, and NC are the refractive indices ofthe lens at the g line, the F line, and the C line. The “d line”, “Cline”, “F line”, and “g line” described in the present specification areemission lines. The wavelength of the d line is 587.56 nm (nanometers)and the wavelength of the C line is 656.27 nm (nanometers), thewavelength of F line is 486.13 nm (nanometers), and the wavelength of gline is 435.84 nm (nanometers).

According to the present disclosure, it is possible to provide a zoomlens, which is reduced in size and has favorable optical performancewhile ensuring a wide angle of view and a high zoom ratio, and animaging apparatus including the zoom lens.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing a configuration of a zoom lensaccording to an embodiment of the present disclosure corresponding tothe zoom lens of Example 1 of the present disclosure.

FIG. 2 is a cross-sectional view showing a configuration of a zoom lensof Example 2 of the present disclosure.

FIG. 3 is a cross-sectional view showing a configuration of a zoom lensof Example 3 of the present disclosure.

FIG. 4 is a cross-sectional view showing a configuration of a zoom lensof Example 4 of the present disclosure.

FIG. 5 is a cross-sectional view showing a configuration of a zoom lensof Example 5 of the present disclosure.

FIG. 6 is a cross-sectional view showing a configuration of a zoom lensof Example 6 of the present disclosure.

FIG. 7 is a cross-sectional view showing a configuration of a zoom lensof Example 7 of the present disclosure.

FIG. 8 is a cross-sectional view showing a configuration of a zoom lensof Example 8 of the present disclosure.

FIG. 9 is a cross-sectional view showing a configuration of a zoom lensof Example 9 of the present disclosure.

FIG. 10 is a cross-sectional view showing a configuration of a zoom lensof Example 10 of the present disclosure.

FIG. 11 is a cross-sectional view showing a configuration of a zoom lensof Example 11 of the present disclosure.

FIG. 12 is a cross-sectional view showing a configuration and rays ofthe zoom lens according to Example 1 of the present disclosure.

FIG. 13 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 1 of the present disclosure.

FIG. 14 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 2 of the present disclosure.

FIG. 15 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 3 of the present disclosure.

FIG. 16 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 4 of the present disclosure.

FIG. 17 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 5 of the present disclosure.

FIG. 18 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 6 of the present disclosure.

FIG. 19 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 7 of the present disclosure.

FIG. 20 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 8 of the present disclosure.

FIG. 21 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 9 of the present disclosure.

FIG. 22 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 10 of the present disclosure.

FIG. 23 shows spherical aberration diagrams, astigmatism diagrams,distortion diagrams, lateral chromatic aberration diagrams of the zoomlens of Example 11 of the present disclosure.

FIG. 24 shows lateral aberration diagrams of the zoom lens according toExample 1 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 25 shows lateral aberration diagrams of the zoom lens according toExample 2 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 26 shows lateral aberration diagrams of the zoom lens according toExample 3 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 27 shows lateral aberration diagrams of the zoom lens according toExample 4 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 28 shows lateral aberration diagrams of the zoom lens according toExample 5 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 29 shows lateral aberration diagrams of the zoom lens according toExample 6 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 30 shows lateral aberration diagrams of the zoom lens according toExample 7 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 31 shows lateral aberration diagrams of the zoom lens according toExample 8 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 32 shows lateral aberration diagrams of the zoom lens according toExample 9 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 33 shows lateral aberration diagrams of the zoom lens according toExample 10 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 34 shows lateral aberration diagrams of the zoom lens according toExample 11 of the present disclosure in a case of no image blurcorrection and in a case of image blur correction.

FIG. 35 is a perspective view of the front side of an imaging apparatusaccording to an embodiment of the present disclosure.

FIG. 36 is a perspective view of the rear side of an imaging apparatusaccording to an embodiment of the present disclosure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the technology of the present disclosurewill be described in detail with reference to the drawings. FIG. 1 is across-sectional view of a lens configuration in each zoom state of azoom lens according to an embodiment of the present disclosure. FIG. 12is a cross-sectional view of a lens configuration and rays in each zoomstate of the zoom lens shown in FIG. 1. The examples shown in FIGS. 1and 12 correspond to the zoom lens of Example 1 to be described later.In FIGS. 1 and 12, the left side is the object side, the right side isthe image side, and a state where an object at infinity is in focus isshown. The upper part labeled “WIDE-ANGLE END” indicates the wide-angleend state, the middle part labeled “MIDDLE” indicates the middle focallength state, and the lower part labeled “TELEPHOTO END” indicates thetelephoto end state. FIG. 12 shows on-axis rays wa and rays with themaximum angle of view wb and wc as the rays in the wide-angle end state,shows on-axis rays ma and rays with the maximum angle of view mb and mcas the rays in the middle focal length state, and shows an on-axis raysto and rays with the maximum angle of view tb and tc as the rays in thetelephoto end state. The rays with the maximum angle of view wb, mb, andtb are rays corresponding to the maximum image height on the negativeside, and the rays with the maximum angle of view wc, mc, and tc arerays corresponding to the maximum image height on the positive side.Here, the positive side and negative side of the image height are theupper side and the lower side of the optical axis Z in FIG. 12.Hereinafter, description will be given mainly with reference to FIG. 1.

FIGS. 1 and 12 show an example in which, assuming that a zoom lens isapplied to an imaging apparatus, an optical member PP having a parallelplate shape is disposed between the zoom lens and the image plane Sim.The optical member PP is a member assumed to include at various filters,a cover glass, and/or the like. The various filters include, forexample, a low pass filter, an infrared cut filter, and a filter thatcuts a specific wavelength region. The optical member PP has norefractive power, and the optical member PP may be configured to beomitted.

The zoom lens of the present disclosure comprises, as lens groups, onlyfive lens groups consisting of, in order from an object side to an imageside along the optical axis Z: a first lens group G1 that has a positiverefractive power; a second lens group G2 that has a negative refractivepower; a third lens group G3 that has a positive refractive power; afourth lens group G4 that has a negative refractive power; and a fifthlens group G5 that has a positive refractive power. In the zoom lens ofthe present disclosure, an aperture stop St is disposed between a lenssurface closest to the image side in the second lens group G2 and a lenssurface closest to the object side in the fourth lens group G4. However,the aperture stop St shown in FIG. 1 does not indicate a shape thereof,but indicates a position thereof on the optical axis.

The zoom lens of the present disclosure employs arrangement of positive,negative, positive, and negative refractive powers in order from theobject side to the image side. Since the refractive power arrangement ofthe lens system is symmetric with respect to the third lens group G3, itis possible to satisfactorily correct distortion and lateral chromaticaberration. Thereby, it is possible to ensure a wide angle of view atthe wide-angle end.

In the zoom lens of the present disclosure, during zooming, by changingall the distances between lens groups adjacent to each other in adirection of the optical axis, at least the first lens group G1, thesecond lens group G2, the third lens group G3, and the fourth lens groupG4 move along the optical axis Z. In the example shown in FIG. 1, duringzooming, the first lens group G1 to the fourth lens group G4 move alongthe optical axis Z along different loci, and the fifth lens group G5remains stationary with respect to the image plane Sim. In the upperdiagram and the middle diagram in FIG. 1, the schematic movementdirection of each lens group during zooming to the long focal lengthside is indicated by an arrow below each lens group that moves duringzooming. A ground symbol is shown below the lens group remainingstationary with respect to the image plane Sim during zooming.

The first lens group G1 consists of, in order from the object side tothe image side, three lenses including a first lens L11 having anegative refractive power, a second lens L12 having a positiverefractive power, and a third lens L13 having a positive refractivepower. Since the first lens group G1 has the above-mentioned three-lensconfiguration, it becomes easy to satisfactorily correct sphericalaberration and longitudinal chromatic aberration at the telephoto end,and field curvature and distortion at the wide-angle end. There is anadvantage in achieving an increase in zoom ratio and an increase inangle of view at the wide-angle end. The first lens L11 and the secondlens L12 may be cemented with each other. In such a configuration, thereis a greater advantage in correcting longitudinal chromatic aberrationat the telephoto end.

For example, in the zoom lens of the example shown in FIG. 1, the secondlens group G2 consists of four lenses L21 to L24 in order from theobject side to the image side, the third lens group G3 consists of fourlenses L31 to L34 in order from the object side to the image side, thefourth lens group G4 consists of two lenses L41 and L42 in order fromthe object side to the image side, and the fifth lens group G5 consistsof three lenses L51 to L53 in order from the object side to the imageside. However, the number of lenses composing each of the second lensgroup G2 to the fifth lens group G5 may be different from the exampleshown in FIG. 1.

The second lens group G2 can be configured to consist of, for example,three negative lenses and one positive lens. In such a configuration,the negative refractive power of the second lens group G2 can be sharedby the three negative lenses, and thus, there is an advantage incorrecting coma aberration and astigmatism. In addition, the second lensgroup G2 includes a negative lens and a positive lens, and thus itbecomes easy to correct chromatic aberration. More specifically, thesecond lens group G2 may be configured to consist of a negative lens, anegative lens, a positive lens, and a negative lens in order from theobject side to the image side.

The third lens group G3 is preferably configured to have an image blurcorrection function. It is preferable that the entire third lens groupG3 or a part of the third lens group G3 moves in a directionintersecting with the optical axis Z for image blur correction. That is,it is preferable that the entire third lens group G3 or a part of thethird lens group G3 moves in a direction intersecting with the opticalaxis Z during image blur correction. Hereinafter, a lens group thatmoves during image blur correction will be referred to as a vibrationreduction lens group.

In order to reduce the size of the zoom lens having arrangement ofpositive, negative, positive, and negative refractive powers in orderfrom the object side to the image side, there is an advantage inincreasing the positive refractive power of the third lens group G3. Insuch a configuration, by providing the vibration reduction lens group inthe third lens group G3, it becomes easy to ensure the refractive powerof the vibration reduction lens group. As a result, it is possible toreduce the amount of movement of the vibration reduction lens groupduring image blur correction. Further, since the aperture stop St isdisposed in the above range, the off-axis ray height in the third lensgroup G3 becomes low. By providing the vibration reduction lens group inthe third lens group G3 having a low off-axis ray height, it is possibleto reduce the diameter of the vibration reduction lens group. Thereby,it is possible to reduce the load on the driving system that drives thevibration reduction lens group, and thereby this configuration is ableto contribute to reduction in size of the apparatus. In order to reducethe load on the driving system of the vibration reduction lens group, itis preferable that the vibration reduction lens group is only the entirethird lens group G3 or only a part of the third lens group G3.

In a case where the vibration reduction lens group is disposed in thethird lens group G3, the third lens group G3 consists of a third lensgroup front group G3F having a positive refractive power and a thirdlens group rear group G3R having a positive refractive power in orderfrom the object side to the image side. Thus, it is preferable that onlythe third lens group rear group G3R moves in a direction intersectingwith the optical axis Z for image blur correction. With theabove-mentioned configuration, the rays converged through the positiverefractive power of the third lens group front group G3F can be madeincident on the third lens group rear group G3R which is the vibrationreduction lens group. Thus, it is possible to keep the diameter of thevibration reduction lens group small.

It should be noted that in the zoom lens having arrangement of positive,negative, positive and negative refractive powers in order from theobject side to the image side, the third lens group G3 mainly takescharge of the convergence effect of the whole system. Thus, in order toachieve reduction in size, it is necessary to increase the refractivepower of the three lens group G3. In a case where the refractive powersof the third lens group front group G3F and the third lens group reargroup G3R are different from each other, it is difficult to ensure therefractive power of the third lens group G3 as a whole. Thus, thisconfiguration is not preferable. Alternatively, the refractive power ofthe lens group on the image side from the third lens group G3 has to beincreased. Thus, it is difficult to satisfactorily correct variousaberrations such as spherical aberration. Thus, this configuration isnot preferable. From the above situations, it is preferable to make therefractive powers of both the third lens group front group G3F and thethird lens group rear group G3R positive.

In a case where the third lens group G3 consists of the above-mentionedthird lens group front group G3F and the third lens group rear group G3Rand only the third lens group rear group G3R is used as the vibrationreduction lens group, it is preferable that the third lens group reargroup G3R consists of one positive lens. By composing the third lensgroup rear group G3R, which is a vibration reduction lens group, of asingle lens, the vibration reduction lens group can be reduced in sizeand weight, and the load on the driving system of the vibrationreduction lens group can be reduced. As a result, the actuator can bereduced in size, and thus the entire apparatus can be reduced in size.

It is preferable that the third lens group front group G3F consists oftwo positive lenses and one negative lens. By forming the third lensgroup front group G3F configured as described above, it becomes easy tosatisfactorily correct spherical aberration and chromatic aberration,even in a case where the refractive power of the third lens group frontgroup G3F is increased for reduction in size, or even in a case wherethe refractive power of the third lens group front group G3F isincreased in order to reduce the ray height of rays incident on thethird lens group rear group G3R which is a vibration reduction lensgroup. Further, by not increasing the number of lenses in the third lensgroup front group G3F more than that in the above-mentionedconfiguration, there is an advantage in achieving reduction in size ofthe whole system.

In the example shown in FIG. 1, the third lens group front group G3Fconsists of lenses L31 to L33, and the third lens group rear group G3Rconsists of a lens L34. The vertical double arrow noted above the lensL34 in the lower diagram of FIG. 1 indicates that the lens L34constitutes a vibration reduction lens group. In the upper and middlediagrams of FIG. 1, the arrows indicating the vibration reduction lensgroups are omitted in order to avoid complication of the diagram.

It is preferable that the fourth lens group G4 consists of one positivelens and one negative lens. In such a case, chromatic aberrationgenerated in the fourth lens group G4 can be corrected satisfactorily.In addition, since the fourth lens group G4 consists of only two lenses,there is an advantage in achieving reduction in the size of the wholesystem. In a case where the fourth lens group G4 consists of only thetwo lenses, the two lenses may be cemented to each other, and there is agreater advantage in achieving reduction in size in the case ofcementing the lenses.

It is preferable that the fourth lens group G4 is configured to performfocusing by moving along the optical axis Z. That is, it is preferablethat only the fourth lens group G4 of the five lens groups moves alongthe optical axis Z during focusing from the object at infinity to theclose-range object. Hereinafter, the lens group that moves duringfocusing is referred to as a focusing lens group. In the example shownin FIG. 1, the fourth lens group G4 moves to the image side duringfocusing from the object at infinity to the close-range object. Thearrow pointing in the right direction noted above the fourth lens groupG4 in the lower diagram of FIG. 1 indicates that the fourth lens groupG4 is a focusing lens group that moves to the image side during focusingfrom the object at infinity to the close-range object. In the upper andmiddle diagrams of FIG. 1, the arrow indicating a focusing lens group isomitted in order to avoid complication of the diagram.

The fourth lens group G4 is a group disposed between two lens groups,such as a third lens group G3 and a fifth lens group G5, having positiverefractive powers, and therefore it becomes easy to reduce the outerlens diameter. By forming the fourth lens group G4 as a focusing lensgroup, it becomes easy to achieve reduction in size and weight of thefocusing lens group. As a result, there is an advantage in achievinghigh-speed autofocusing, and it is possible to reduce the load on thedriving system of the focusing lens group.

For example, the fifth lens group G5 can be configured to consist of twopositive lenses and one negative lens. In such as case, there is anadvantage in satisfactorily correcting lateral chromatic aberration andfield curvature. In the above case where the fifth lens group G5consists of three lenses, the fifth lens group G5 may be configured toconsist of, in order from the object side to the image side, a cementedlens, in which a positive lens and a negative lens are cemented in orderfrom the object side, and a single lens which has a positive refractivepower.

Alternatively, the fifth lens group G5 can be configured to consist ofone positive lens. In such a case, there is an advantage in reduction insize.

The fifth lens group G5 may be configured to remain stationary withrespect to the image plane Sim during zooming. By adopting aconfiguration in which the lens group disposed to be closest to theimage side remains stationary during zooming, intrusion of dust and thelike can be reduced.

Alternatively, the fifth lens group G5 may be configured to move alongthe optical axis Z during zooming. In such a case, the degree of freedomof aberration correction increases, and the optical performance can befurther improved.

Next, a configuration relating to Conditional Expressions will bedescribed. In the zoom lens of the present disclosure, assuming that afocal length of the first lens group G1 is f1 and a focal length of thefifth lens group G5 is f5, it is preferable to satisfy ConditionalExpression (1). By not allowing the result of Conditional Expression (1)to be equal to or less than the lower limit value, the refractive powerof the first lens group G1 can be prevented from becoming excessivelystrong. Thus, in particular, it becomes easy to satisfactorily correctthe spherical aberration and the longitudinal chromatic aberration atthe telephoto end. Alternatively, by not allowing the result ofConditional Expression (1) to be equal to or less than the lower limitvalue, the refractive power of the fifth lens group G5 can be preventedfrom becoming excessively weak. Thus, it is possible to prevent theincident angle of the off-axis principal rays incident on the imagingelement disposed on the image plane Sim from becoming excessively large.As a result, it is possible to reduce shading. By not allowing theresult of Conditional Expression (1) to be equal to or greater than theupper limit value, the refractive power of the first lens group G1 canbe prevented from becoming excessively weak. Thus, it is possible tominimize the amount of movement of the first lens group G1 duringzooming. As a result, it is possible to reduce the size of the lenssystem. Alternatively, by not allowing the result of ConditionalExpression (1) to be equal to or greater than the upper limit value, therefractive power of the fifth lens group G5 can be prevented frombecoming excessively strong. Thus, it becomes easy to satisfactorilycorrect field curvature and distortion at the wide-angle end. Inaddition, in a case of a configuration in which Conditional Expression(1-1) is satisfied, it is possible to obtain more favorablecharacteristics. In a case of a configuration in which ConditionalExpression (1-2) is satisfied, it is possible to obtain further morefavorable characteristics.

0.4<f1/f5<2  (1)

0.45<f1/f5<1.8  (1-1)

0.5<f1/f5<1.6  (1-2)

In the zoom lens of the present disclosure, assuming that a focal lengthof the fourth lens group G4 is f4 and a focal length of the fifth lensgroup G5 is f5, Conditional Expression (2) is satisfied. By not allowingthe result of Conditional Expression (2) to be equal to or less than thelower limit value, the refractive power of the fourth lens group G4 canbe prevented from becoming excessively weaker than the refractive powerof the fifth lens group G5. Thus, it becomes easy to suppressfluctuation in chromatic aberration during zooming while satisfactorilycorrecting astigmatism and field curvature. By not allowing the resultof Conditional Expression (2) to be equal to or greater than the upperlimit value, the refractive power of the fourth lens group G4 can beprevented from becoming excessively stronger than the refractive powerof the fifth lens group G5. Thus, it becomes easy to satisfactorilycorrect spherical aberration. In addition, in a case of a configurationin which Conditional Expression (2-1) is satisfied, it is possible toobtain more favorable characteristics. In a case of a configuration inwhich Conditional Expression (2-2) is satisfied, it is possible toobtain further more favorable characteristics.

−0.7<f4/f5<−0.1  (2)

−0.64<f4/f5<−0.15  (2−1)

−0.58<f4/f5<−0.2  (2−2)

In the zoom lens of the present disclosure, assuming that a refractiveindex of the second lens L12 at the d line is Nd2, ConditionalExpression (3) is satisfied. By not allowing the result of ConditionalExpression (3) to be equal to or less than the lower limit value, itbecomes easy to achieve reduction in size of the lens system. By notallowing the result of Conditional Expression (3) to be equal to orgreater than the upper limit value, it becomes easy to satisfactorilycorrect longitudinal chromatic aberration. In addition, in a case of aconfiguration in which Conditional Expression (3-1) is satisfied, it ispossible to obtain more favorable characteristics. In a case of aconfiguration in which Conditional Expression (3-2) is satisfied, it ispossible to obtain further more favorable characteristics.

1.6<Nd2<2  (3)

1.62<Nd2<1.96  (3-1)

1.63<Nd2<1.93  (3-2)

It is preferable that the zoom lens of the present disclosure satisfiesthe following conditional expressions. Assuming that a back focal lengthat an air conversion distance in a state where an object at infinity isin focus at a wide-angle end is BFw, and a sum of a distance on theoptical axis from a lens surface closest to the object side to a lenssurface closest to the image side and the back focal length at the airconversion distance in the state where the object at infinity is infocus at the wide-angle end is TLw, it is preferable to satisfyConditional Expression (4). By not allowing the result of ConditionalExpression (4) to be equal to or less than the lower limit value, itbecomes easy to ensure the back focal length necessary for theinterchangeable lens camera or the like. By not allowing the result ofConditional Expression (4) to be equal to or greater than the upperlimit value, the back focal length can be prevented from becomingexcessively long, and a range where a lens can be disposed can be set tobe increased in the total optical length. Therefore, it is possible toensure the range of movement of each lens group during zooming. Thereby,the refractive power of each lens group can be prevented from becomingexcessively strong. Thus, it becomes easy to ensure favorable opticalperformance by suppressing various aberrations. In addition, in a caseof a configuration in which Conditional Expression (4-1) is satisfied,it is possible to obtain more favorable characteristics.

0.07<BFw/TLw<0.25  (4)

0.1<BFw/TLw<0.23  (4-1)

The third lens group G3 consists of, in order from the object side tothe image side, a third lens group front group G3F having a positiverefractive power and a third lens group rear group G3R having a positiverefractive power, and only the third lens group rear group G3R is thevibration reduction lens group. In such a configuration, the followingis preferable. That is, assuming that a focal length of the third lensgroup rear group G3R is f3R and a focal length of the third lens groupfront group G3F is f3F, Conditional Expression (5) is satisfied. By notallowing the result of Conditional Expression (5) to be equal to or lessthan the lower limit value, the refractive power of the third lens grouprear group G3R can be prevented from becoming excessively strong. By notallowing the result of Conditional Expression (5) to be equal to orgreater than the upper limit value, the refractive power of the thirdlens group front group G3F can be prevented from becoming excessivelystrong. By setting f3R/f3F within the range of Conditional Expression(5), the positive refractive power of the third lens group G3 can beappropriately distributed to the third lens group front group G3F andthe third lens group rear group G3R. Thus, it is possible to reduce thedifference in the spherical aberration curve due to the wavelengthduring zooming. Further, it is possible to suppress the sensitivity ofdeterioration in performance due to assembly errors such as relativetilt between the third lens group front group G3F and the third lensgroup rear group G3R. Furthermore, the sensitivity of image blurcorrection can be set appropriately, and it is possible tosatisfactorily suppress fluctuation in aberrations during image blurcorrection. In addition, in a case of a configuration in whichConditional Expression (5-1) is satisfied, it is possible to obtain morefavorable characteristics.

0.1<f3R/f3F<0.9  (5)

0.15<f3R/f3F<0.8  (5-1)

The third lens group G3 consists of, in order from the object side tothe image side, a third lens group front group G3F having a positiverefractive power and a third lens group rear group G3R having a positiverefractive power, and only the third lens group rear group G3R is thevibration reduction lens group. In such a configuration, the followingis preferable. That is, assuming that a lateral magnification of thethird lens group rear group G3R in a state where an object at infinityis in focus at a telephoto end is β3Rt, and a combined lateralmagnification of the fourth lens group G4 and the fifth lens group G5 inthe state where the object at infinity is in focus at the telephoto endis β45t, Conditional Expression (6) is satisfied. (1−β3Rt)×β45t ofConditional Expression (6) indicates the amount of image movement on theimage plane Sim, that is, the vibration reduction sensitivity withrespect to the amount of movement of the vibration reduction lens groupin the direction perpendicular to the optical axis Z. ConditionalExpression (6) is an expression indicating a preferable range of thevibration reduction sensitivity. By not allowing the result ofConditional Expression (6) to be equal to or less than the lower limitvalue, it is possible to reduce the amount of movement of the vibrationreduction lens group during image blur correction. Thereby, bysuppressing an increase in the diameter of the vibration reduction lensgroup, it is possible to reduce the load on the driving system thatdrives the vibration reduction lens group. By not allowing the result ofConditional Expression (6) to be equal to or greater than the upperlimit value, it is possible to suppress the sensitivity of deteriorationin performance due to assembly errors such as relative tilt between thevibration reduction lens group and the lens group disposed on the objectside and the image side. Further, in a case where the vibrationreduction sensitivity becomes excessively high, a problem arises in thatit may be difficult to stably perform image blur correction. However, bynot allowing the result of Conditional Expression (6) to be equal to orgreater than the upper limit value, such a problem can be prevented. Inaddition, in a case of a configuration in which Conditional Expression(6-1) is satisfied, it is possible to obtain more favorablecharacteristics.

2<(1−β3Rt)×β45t<5  (6)

2.3<(1−β3Rt)×β45t<4.5  (6-1)

The third lens group G3 consists of, in order from the object side tothe image side, a third lens group front group G3F having a positiverefractive power and a third lens group rear group G3R having a positiverefractive power, and only the third lens group rear group G3R is thevibration reduction lens group. In such a configuration, the followingis preferable. That is, assuming that Abbe number of at least onepositive lens included in the third lens group rear group G3R based onthe d line is νd3Rp, Conditional Expression (7) is satisfied. By notallowing the result of Conditional Expression (7) to be equal to or lessthan the lower limit value, it is possible to suppress fluctuation inchromatic aberration during image blur correction. By not allowing theresult of Conditional Expression (7) to be equal to or greater than theupper limit value, the refractive index of the material composing thepositive lens can be prevented from becoming excessively low, and thelens can be made thinner. Therefore, this configuration is able tocontribute to reduction in size. In addition, in a case of aconfiguration in which Conditional Expression (7-1) is satisfied, it ispossible to obtain more favorable characteristics. In a case of aconfiguration in which Conditional Expression (7-2) is satisfied, it ispossible to obtain further more favorable characteristics.

65≤νd3Rp<105  (7)

72<νd3Rp>100  (7-1)

80<νd3Rp>98  (7-2)

In a configuration in which only the fourth lens group G4 is used as thefocusing lens group, assuming that a lateral magnification of the fourthlens group G4 in a state where an object at infinity is in focus at atelephoto end is (Mt, and a lateral magnification of the fifth lensgroup G5 in the state where the object at infinity is in focus at thetelephoto end is β5t, it is preferable to satisfy Conditional Expression(8). (1−β4t²)×β5t² of Conditional Expression (8) indicates the amount offocus shift, that is, the focus sensitivity with respect to the amountof movement of the fourth lens group G4 in the direction of the opticalaxis, which is the focusing lens group, at the telephoto end.Conditional Expression (8) is an expression indicating a preferablerange of the focus sensitivity. By not allowing the result ofConditional Expression (8) to be equal to or less than the lower limitvalue, it is possible to suppress the sensitivity of deterioration inperformance to the eccentric error of the fourth lens group G4. Further,by not allowing the result of Conditional Expression (8) to be equal toor less than the lower limit value, the refractive power of the fourthlens group G4 is easily prevented from becoming excessively strong.Thus, there is an advantage in satisfactorily correcting sphericalaberration. By not allowing the result of Conditional Expression (8) tobe equal to or greater than the upper limit value, the amount ofmovement of the fourth lens group G4 during focusing can be reduced, andthe speed of autofocusing can be increased or the shortest imagingdistance can be reduced. In addition, in a case of a configuration inwhich Conditional Expression (8-1) is satisfied, it is possible toobtain more favorable characteristics. In a case of a configuration inwhich Conditional Expression (8-2) is satisfied, it is possible toobtain further more favorable characteristics.

−7<(1−β4t ²)×β5t ²<−2.6  (8)

−6.5<(1−β4t ²)×β5t ²<−2.8  (8-1)

−6.2<(1−β4t ²)×β5t ²<−3  (8-2)

In a configuration in which the fourth lens group G4 consists of onepositive lens and one negative lens, assuming that an Abbe number of thenegative lens of the fourth lens group G4 based on the d line is νd4n,and an Abbe number of the positive lens of the fourth lens group G4based on the d line is νd4p, it is preferable to satisfy ConditionalExpression (9). By not allowing the result of Conditional Expression (9)to be equal to or less than the lower limit value, the differencebetween the dispersion of the positive lens and the dispersion of thenegative lens composing the fourth lens group G4 is prevented frombecoming excessively small. As a result, it is possible tosatisfactorily correct chromatic aberration, particularly, lateralchromatic aberration. By not allowing the result of ConditionalExpression (9) to be equal to or greater than the upper limit value, therefractive index of the material used for the negative lens of thefourth lens group G4 can be prevented from becoming lower. Therefore,there is an advantage in satisfactorily correcting field curvature. Inaddition, in a case of a configuration in which Conditional Expression(9-1) is satisfied, it is possible to obtain more favorablecharacteristics.

5<νd4n−νd4p<26  (9)

7<νd4n−νd4p<24  (9-1)

Assuming that a sum of the distance on the optical axis from the lenssurface closest to the object side to the lens surface closest to theimage side and the back focal length at the air conversion distance in astate where an object at infinity is in focus at a wide-angle end isTLw, and a maximum image height is Y, it is preferable to satisfyConditional Expression (10). For example, the maximum image height Y isshown in FIG. 12. By not allowing the result of Conditional Expression(10) to be equal to or less than the lower limit value, the refractivepower of each group can be prevented from becoming excessively strong.Therefore, it becomes easy to satisfactorily correct various aberrationssuch as spherical aberration. Alternatively, by not allowing the resultof Conditional Expression (10) to be equal to or less than the lowerlimit value, a lens necessary for ensuring high optical performanceand/or a high zoom ratio can be disposed. By not allowing the result ofConditional Expression (10) to be equal to or greater than the upperlimit value, the lens system can be configured to have a small size. Inaddition, in a case of a configuration in which Conditional Expression(10-1) is satisfied, it is possible to obtain more favorablecharacteristics. In a case of a configuration in which ConditionalExpression (10-2) is satisfied, it is possible to obtain further morefavorable characteristics.

6<TLw/|Y|<8.6  (10)

6.2<TLw/|Y|<8  (10-1)

6.4<TLw/|Y|<7.6  (10-2)

Assuming that a distance on the optical axis between the fourth lensgroup G4 and the fifth lens group G5 in a state where an object atinfinity is in focus at a telephoto end is D45t, and a distance on theoptical axis between the fourth lens group G4 and the fifth lens groupG5 in the state where the object at infinity is in focus at thewide-angle end is D45w, it is preferable to satisfy ConditionalExpression (11). By not allowing the result of Conditional Expression(11) to be equal to or less than the lower limit value, it is possibleto satisfactorily suppress fluctuation in field curvature duringzooming. By not allowing the result of Conditional Expression (11) to beequal to or greater than the upper limit value, it is possible to reducefluctuation in chromatic aberration during zooming. In addition, in acase of a configuration in which Conditional Expression (11-1) issatisfied, it is possible to obtain more favorable characteristics.

2<D45t/D45w<13  (11)

3<D45t/D45w<12  (11-1)

Assuming that a back focal length at an air conversion distance in astate where an object at infinity is in focus at a wide-angle end isBFw, a focal length of the zoom lens in the state where the object atinfinity is in focus at the wide-angle end is fw, and a maximum halfangle of view in the state where the object at infinity is in focus atthe wide-angle end is ωw, it is preferable to satisfy ConditionalExpression (12). For example, FIG. 12 shows the maximum half angle ofview ωw. By not allowing the result of Conditional Expression (12) to beequal to or less than the lower limit value, it is possible to ensurethe back focal length necessary for the interchangeable lens camera orthe like. By not allowing the result of Conditional Expression (12) tobe equal to or greater than the upper limit value, the back focal lengthcan be prevented from becoming excessively long, and a range where alens can be disposed can be set to be increased in the total opticallength. Therefore, it is possible to ensure the range of movement ofeach lens group during zooming. Thereby, the refractive power of eachlens group can be prevented from becoming excessively strong. Thus, itbecomes easy to ensure favorable optical performance by suppressingvarious aberrations. In addition, in a case of a configuration in whichConditional Expression (12-1) is satisfied, it is possible to obtainmore favorable characteristics. In a case of a configuration in whichConditional Expression (12-2) is satisfied, it is possible to obtainfurther more favorable characteristics.

0.5<BFw/(fw×tan|ωw|)<1.6  (12)

0.6<BFw/(fw×tan|ωw|)<1.5  (12-1)

0.7<BFw/(fw×tan|ωw|)<1.4  (12-2)

Assuming that an average of a refractive index of the second lens L12 atthe d line and a refractive index of the third lens L13 at the d line inthe first lens group G1 is NdG1p, it is preferable to satisfyConditional Expression (12). By not allowing the result of ConditionalExpression (12) to be equal to or less than the lower limit value, itbecomes easy to achieve reduction in size of the lens system. By notallowing the result of Conditional Expression (13) to be equal to orgreater than the upper limit value, it becomes easy to satisfactorilycorrect longitudinal chromatic aberration. In addition, in a case of aconfiguration in which Conditional Expression (13-1) is satisfied, it ispossible to obtain more favorable characteristics.

1.63<NdG1p<1.9  (13)

1.64<NdG1p<1.85  (13-1)

Assuming that a focal length of the second lens group G2 is f2, and afocal length of the third lens group G3 is f3, it is preferable tosatisfy Conditional Expression (14). By not allowing the result ofConditional Expression (14) to be equal to or less than the lower limitvalue, the amount of movement of the second lens group G2 during zoomingcan be reduced, or the second lens group G2 can be formed to have astrong zooming effect. By not allowing the result of ConditionalExpression (14) to be equal to or greater than the upper limit value, inparticular, it becomes easy to satisfactorily correct lateral chromaticaberration at the wide-angle end. In addition, in a case of aconfiguration in which Conditional Expression (14-1) is satisfied, it ispossible to obtain more favorable characteristics.

−1.3<f2/f3<−0.4  (14)

−1.1<f2/f3<−0.5  (14−1)

Assuming that a focal length of the first lens group G1 is f1, and afocal length of the second lens group G2 is f2, it is preferable tosatisfy Conditional Expression (15). By not allowing the result ofConditional Expression (15) to be equal to or less than the lower limitvalue, the amount of movement of the first lens group G1 during zoomingand the effective diameter of the lens closest to the object side arereduced. As a result, it becomes easy to achieve reduction in size ofthe whole system. By not allowing the result of Conditional Expression(15) to be equal to or greater than the upper limit value, it becomeseasy to satisfactorily correct the spherical aberration and thelongitudinal chromatic aberration at the telephoto end. In addition, ina case of a configuration in which Conditional Expression (15-1) issatisfied, it is possible to obtain more favorable characteristics. In acase of a configuration in which Conditional Expression (15-2) issatisfied, it is possible to obtain further more favorablecharacteristics.

−8<f1/f2<−3  (15)

−7.3<f1/f2<−3.5  (15−1)

−6.6<f1/f2<−4  (15−2)

Assuming that a focal length of the third lens group G3 is f3 and afocal length of the fourth lens group G4 is f4, it is preferable tosatisfy Conditional Expression (16). The third lens group G3 and thefourth lens group G4 are lens groups each of which has a relatively highray height of the on-axis marginal rays. By satisfying ConditionalExpression (16), the ratio between a positive refractive power of thethird lens group G3 and a negative refractive power of the fourth lensgroup G4 can be appropriately set. Therefore, it is possible tosatisfactorily correct spherical aberration. In addition, in a case of aconfiguration in which Conditional Expression (16-1) is satisfied, it ispossible to obtain more favorable characteristics.

−0.9<f3/f4<−0.4  (16)

−0.8<f3/f4<−0.5  (16-1)

Assuming that a focal length of the second lens group G2 is f2 and afocal length of the fourth lens group G4 is f4, it is preferable tosatisfy Conditional Expression (17). By not allowing the result ofConditional Expression (17) to be equal to or less than the lower limitvalue, the refractive power of the second lens group G2 can be preventedfrom becoming excessively strong. Thus, it is possible to reducefluctuation in distortion and fluctuation in field curvature duringzooming. By not allowing the result of Conditional Expression (17) to beequal to or greater than the upper limit value, the refractive power ofthe fourth lens group G4 can be prevented from becoming excessivelystrong. Thus, it becomes easy to satisfactorily correct sphericalaberration. In addition, in a case of a configuration in whichConditional Expression (17-1) is satisfied, it is possible to obtainmore favorable characteristics.

0.2<f2/f4<0.8  (17)

0.3<f2/f4<0.7  (17-1)

The third lens group G3 consists of, in order from the object side tothe image side, a third lens group front group G3F having a positiverefractive power and a third lens group rear group G3R having a positiverefractive power, and only the third lens group rear group G3R is thevibration reduction lens group. In such a configuration, the followingis preferable. That is, assuming that a focal length of the third lensgroup rear group G3R is f3R and a focal length of the third lens groupG3 is f3, Conditional Expression (18) is satisfied. By not allowing theresult of Conditional Expression (18) to be equal to or less than thelower limit value, the refractive power of the vibration reduction lensgroup can be prevented from becoming excessively strong. Thus, it ispossible to suppress fluctuation in coma aberration and fluctuation inchromatic aberration in a case where the vibration reduction lens groupmoves. Further, the image blur correction stability can be preventedfrom being lowered due to the vibration reduction sensitivity that hasbecome excessively high. By not allowing the result of ConditionalExpression (18) to be equal to or greater than the upper limit value,the refractive power of the vibration reduction lens group can beprevented from becoming excessively weak. Thus, it is possible to reducethe amount of movement of the vibration reduction lens group duringimage blur correction. In addition, in a case of a configuration inwhich Conditional Expression (18-1) is satisfied, it is possible toobtain more favorable characteristics. In a case of a configuration inwhich Conditional Expression (18-2) is satisfied, it is possible toobtain further more favorable characteristics.

0.6<f3R/f3<1.8  (18)

0.7<f3R/f3<1.6  (18-1)

0.8<f3R/f3<1.4  (18-2)

In a configuration in which only the fourth lens group G4 is used as thefocusing lens group, assuming that a lateral magnification of the fourthlens group G4 in a state where an object at infinity is in focus at thewide-angle end is f34w, and a lateral magnification of the fifth lensgroup G5 in the state where the object at infinity is in focus at thewide-angle end is f35w, it is preferable to satisfy ConditionalExpression (19). (1−β4w²)×β5w² of Conditional Expression (19) indicatesthe amount of focus shift, that is, the focus sensitivity with respectto the amount of movement of the fourth lens group G4 in the directionof the optical axis, which is the focusing lens group, at the wide-angleend. Conditional Expression (19) is an expression indicating apreferable range of the focus sensitivity. By not allowing the result ofConditional Expression (19) to be equal to or less than the lower limitvalue, it is possible to suppress the sensitivity of deterioration inperformance to the eccentric error of the fourth lens group G4. Further,by not allowing the result of Conditional Expression (19) to be equal toor less than the lower limit value, the refractive power of the fourthlens group G4 is easily prevented from becoming excessively strong.Thus, there is an advantage in satisfactorily correcting sphericalaberration. By not allowing the result of Conditional Expression (19) tobe equal to or greater than the upper limit value, the amount ofmovement of the fourth lens group G4 during focusing can be reduced.Therefore, this configuration is able to contribute to reduction intotal optical length at the wide-angle end. In addition, it is possibleto increase the speed of autofocusing. In addition, in a case of aconfiguration in which Conditional Expression (19-1) is satisfied, it ispossible to obtain more favorable characteristics.

−3.1<(1−β4w ²)×β5w ²<−1.2  (19)

−2.8<(1−β4w ²)×β5w ²<−1.4  (19-1)

Assuming that an Abbe number of the first lens in the first lens groupG1 based on the d line is νd1, it is preferable to satisfy ConditionalExpression (20). By not allowing the result of Conditional Expression(20) to be equal to or less than the lower limit value, in particular,it is possible to satisfactorily correct longitudinal chromaticaberration at the telephoto end. In addition, in a case where the Abbenumber of the negative first lens increases and the difference betweenthe Abbe number of the negative first lens and the Abbe number of thepositive second lens decreases, it is necessary to make the refractivepowers of the first lens and the second lens strong in order to correctlongitudinal chromatic aberration. However, in a case where therefractive powers are made strong, spherical aberration and fieldcurvature increase. By not allowing the result of Conditional Expression(20) to be equal to or greater than the upper limit value, in order tocorrect longitudinal chromatic aberration, the refractive powers of thefirst lens and the second lens can be prevented from becomingexcessively strong. Thus, in particular, there is an advantage insatisfactorily correcting spherical aberration and field curvature onthe telephoto side. In addition, in a case of a configuration in whichConditional Expression (20-1) is satisfied, it is possible to obtainmore favorable characteristics.

15<νd1<26  (20)

16<νd1<25  (20-1)

The fourth lens group G4 consists of at least one positive lens and atleast one negative lens. In this configuration, assuming that an Abbenumber of the positive lens in the fourth lens group G4 based on the dline is νd4p, it is preferable that the fourth lens group G4 has atleast one positive lens that satisfies Conditional Expression (21). Bynot allowing the result of Conditional Expression (21) to be equal to orless than the lower limit value, it becomes easy to satisfactorilycorrect longitudinal chromatic aberration on the telephoto side,particularly, chromatic aberration on the short wavelength side. Inaddition, in a case where the Abbe number of the positive lens in thefourth lens group G4 increases and the difference between the Abbenumber of the positive lens and the Abbe number of the negative lens inthe fourth lens group G4 decreases, in order to correct longitudinalchromatic aberration, it is necessary to make both the refractive powersof these positive and negative lenses strong. However, in a case wherethe refractive powers are made strong, spherical aberration and comaaberration become large. By not allowing the result of ConditionalExpression (21) to be equal to or greater than the upper limit value,the refractive power of each of the lenses composing the fourth lensgroup G4 can be prevented from becoming excessively strong. Thus, inparticular, there is an advantage in satisfactorily correcting fifth orhigher order spherical aberration and coma aberration on the telephotoside. In addition, in a case of a configuration in which ConditionalExpression (21-1) is satisfied, it is possible to obtain more favorablecharacteristics.

15<νd4p<28  (21)

16<νd4p<26  (21-1)

The above-mentioned preferred configurations and availableconfigurations may be optional combinations, and it is preferable toselectively adopt the configurations in accordance with requiredspecification. According to the technique of the present disclosure, itis possible to achieve a zoom lens that is reduced in size and hasfavorable optical performance while ensuring a wide angle of view and ahigh zoom ratio. It should be noted that the term “wide angle of view”described herein means that the maximum half angle of view at thewide-angle end is 40 degrees or more, and the term “high zoom ratio”means that the zoom ratio is 4 times or more.

Next, numerical examples of the zoom lens of the present disclosure willbe described.

Example 1

FIG. 1 is a cross-sectional view of a zoom lens of Example 1, and anillustration method and a configuration thereof is as described above.Therefore, repeated description is partially omitted herein. The zoomlens of Example 1 consists of, in order from the object side to theimage side, a first lens group G1 having a positive refractive power, asecond lens group G2 having a negative refractive power, an aperturestop St, a third lens group G3 having a negative refractive power, afourth lens group G4 having a negative refractive power, and a fifthlens group G5 having a positive refractive power. The third lens groupG3 consists of, in order from the object side to the image side, a thirdlens group front group G3F having a positive refractive power and athird lens group rear group G3R having a positive refractive power. Thefirst lens group G1 consists of three lenses of a first lens L11, asecond lens L12, and a third lens L13 in order from the object side tothe image side. The second lens group G2 consists of four lenses L21 toL24 in order from the object side to the image side. The third lensgroup front group G3F consists of three lenses L31 to L33 in order fromthe object side to the image side. The third lens group rear group G3Rconsists of one lens L34. The fourth lens group G4 consists of twolenses L41 and L42 in order from the object side to the image side. Thefifth lens group G5 consists of three lenses L51 to L53 in order fromthe object side to the image side. During zooming from the wide-angleend to the telephoto end, the first lens group G1, the second lens groupG2, the third lens group G3, and the fourth lens group G4 move along theoptical axis Z by changing all the distances between lens groupsadjacent to each other in the direction of the optical axis, and thefifth lens group G5 remains stationary with respect to the image planeSim. The vibration reduction lens group consists of only the third lensgroup rear group G3R. The focusing lens group consists of only thefourth lens group G4. The outline of the zoom lens of Example 1 has beendescribed above.

Regarding the zoom lens of Example 1, Table 1 shows basic lens data,Table 2 shows specification and variable surface distances, and Table 3shows aspheric surface coefficients thereof. In Table 1, the column ofSn shows surface numbers. The surface closest to the object side is thefirst surface, and the surface numbers increase one by one toward theimage side. The column of R shows radii of curvature of the respectivesurfaces. The column of D shows surface distances on the optical axisbetween the respective surfaces and the surfaces adjacent to the imageside. Further, the column of Nd shows a refractive index of eachconstituent element at the d line, the column of νd shows an Abbe numberof each constituent element based on the d line, and the column of θgFshows a partial dispersion ratio of each constituent element between theg line and the F line.

In Table 1, the sign of the radius of curvature of the surface convextoward the object side is positive and the sign of the radius ofcurvature of the surface convex toward the image side is negative. Table1 also shows the optical member PP and the aperture stop St, and in aplace of a surface number of a surface corresponding to the aperturestop St, the surface number and a term of (St) are noted. A value at thebottom place of D in Table 1 indicates a distance between the imageplane Sim and the surface closest to the image side in the table. InTable 1, the variable surface distances, which are distances variableduring zooming, are referenced by the reference signs DD[ ], and arewritten into places of D, where object side surface numbers of distancesare noted in [ ].

Table 2 shows values of the zoom ratio Zr, the focal length f, the Fnumber FNo, the maximum total angle of view 2ω, and the variable surfacedistance during zooming. (°) in the place of 2ω indicates that the unitthereof is a degree. In Table 2, the values in the wide-angle end state,the middle focal length state, and the telephoto end state are shown inthe columns denoted as “Wide-Angle End”, “Middle”, and “Telephoto End”,respectively. The values shown in Tables 1 and 2 are values in the caseof using the d line as a reference in a state where the object atinfinity is in focus.

In Table 1, the reference sign * is attached to surface numbers ofaspheric surfaces, and numerical values of the paraxial radius ofcurvature are written into the column of the radius of curvature of theaspheric surface. In Table 3, the row of Sn shows surface numbers of theaspheric surfaces, and the rows of KA and Am (m=3, 4, 5, . . . , 10)shows numerical values of the aspheric surface coefficients for eachaspheric surface. The “E±n” (n: an integer) in numerical values of theaspheric surface coefficients of Table 3 indicates “×10^(±n)”. KA and Amare the aspheric surface coefficients in the aspheric surface expressionrepresented by the following expression.

Zd=C×h ²/{1+(1−KA×C ² ×h ²)^(1/2) }+ΣAm×h ^(m)

Here, Zd is an aspheric surface depth (a length of a perpendicular froma point on an aspheric surface at height h to a plane that isperpendicular to the optical axis and contacts with the vertex of theaspheric surface),

-   -   h is a height (a distance from the optical axis to the lens        surface),    -   C is an inverse of paraxial radius of curvature,    -   KA and Am are aspheric surface coefficients, and    -   Σ in the aspheric surface expression means the sum with respect        to m.

In data of each table, a degree is used as a unit of an angle, and mm(millimeter) is used as a unit of a length, but appropriate differentunits may be used since the optical system can be used even in a casewhere the system is enlarged or reduced in proportion. Further, each ofthe following tables shows numerical values rounded off to predetermineddecimal places.

TABLE 1 Example 1 Sn R D Nd νd θgF 1 147.65954 1.500 1.84666 23.780.62054 2 66.26836 5.470 1.75976 52.02 0.54640 3 413.58552 0.150 461.13525 4.830 1.74437 53.56 0.54443 5 210.90455 DD[5]  *6 293.872191.500 1.80998 40.95 0.56644 *7 13.80754 8.421 8 −17.04404 0.700 1.6665656.91 0.54500 9 −55.15886 0.705 10 117.74408 3.699 1.94595 17.98 0.6546011 −39.74485 1.406 12 −20.28011 0.700 1.84700 22.65 0.62089 13 −30.35505DD[13] 14(St) ∞ 0.500 *15 19.72898 4.886 1.68948 31.02 0.59874 *16−228.86837 2.415 17 35.75828 0.700 1.85896 22.73 0.62844 18 11.375843.606 1.61800 63.33 0.54414 19 19.94929 1.600 *20 17.11541 5.718 1.4970081.61 0.53887 *21 −22.47607 DD[21] 22 78.01772 2.000 1.85896 22.730.62844 23 −105.36171 0.610 1.80440 39.59 0.57297 24 20.27468 DD[24] 25119.51326 3.106 1.61807 47.62 0.56442 26 −75.27031 1.300 1.81996 46.010.55579 27 120.38400 0.933 *28 −109.16204 3.553 1.58313 59.38 0.54237*29 −31.21099 14.685  30 ∞ 2.850 1.51680 64.20 0.53430 31 ∞ 1.000

TABLE 2 Example 1 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.504 36.548 77.783 FNo. 4.12 4.13 4.13 2ω(°) 87.2 40.8 19.8DD[5] 0.800 14.741 35.652 DD[13] 19.488 6.274 1.188 DD[21] 2.496 3.8402.495 DD[24] 3.861 17.125 31.386

TABLE 3 Example 1 Sn 6 7 15 16 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −2.0156062E−05  −5.1708119E−05  −3.7833014E−05 −2.8854059E−05  A5 3.1332925E−06 3.8228839E−06 8.9432918E−061.2730218E−05 A6 1.0876565E−07 −1.1063845E−08  −1.8848688E−06 −3.2220609E−06  A7 −1.7774067E−08  −2.4210034E−08  8.0755296E−082.5722342E−07 A8 −2.0072742E−11  3.3662549E−09 1.2507349E−081.3197679E−08 A9 3.3457813E−11 −3.8954053E−11  −1.2306669E−09 −3.4051477E−09  A10 −3.6041271E−13  −1.1521318E−11  −1.3124899E−11 1.2147994E−10 Sn 20 21 28 29 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −3.8001832E−05  3.2816072E−05 9.9652891E−063.7008339E−05 A5 −1.4671735E−05  −1.2839953E−05  5.3568193E−06−1.8060076E−06  A6 8.9777112E−06 7.3318923E−06 −5.3160786E−07 2.4328182E−07 A7 −2.5684771E−06  −1.9257261E−06  1.2498677E−08−1.2493449E−09  A8 3.9432287E−07 2.7375207E−07 1.8271499E−09−1.5154824E−09  A9 −3.1518780E−08  −2.0706246E−08  −1.7695720E−10 6.3461976E−11 A10 1.0102143E−09 6.3878265E−10 4.9789359E−12−2.0584295E−15 

FIGS. 13 and 24 each show aberration diagrams in a state where an objectat infinity is brought into focus through the zoom lens of Example 1.FIG. 13 shows aberration diagrams in a state where there is no imageblur correction. In FIG. 13, in order from the left side, sphericalaberration, astigmatism, distortion, and lateral chromatic aberrationare shown. In FIG. 13, the upper part labeled “WIDE-ANGLE END” indicatesaberrations in the wide-angle end state, the middle part labeled“MIDDLE” indicates aberrations in the middle focal length state, and thelower part labeled “TELEPHOTO END” indicates aberrations in thetelephoto end state. In the spherical aberration diagram, aberrations atthe d line, the C line, the F line, and the g line are indicated by thesolid line, the long dashed line, the short dashed line, and the chainline, respectively. In the astigmatism diagram, aberration in thesagittal direction at the d line is indicated by the solid line, andaberration in the tangential direction at the d line is indicated by theshort dashed line. In the distortion diagram, aberration at the d lineis indicated by the solid line. In the lateral chromatic aberration,aberrations at the C line, the F line, and the g line are respectivelyindicated by the long dashed line, the short dashed line, and the chainline. In the spherical aberration diagram, FNo. indicates an F number.In the other aberration diagrams, ω indicates a half angle of view.

FIG. 24 shows ten lateral aberrations in a case where there is no imageblur correction on the left side labeled “NO IMAGE BLUR CORRECTION”, andshows ten lateral aberrations in a case where the vibration reductionlens group is moved in the direction perpendicular to the optical axis Zby an amount corresponding to a ray tilt of −0.3 degrees on the rightside labeled “IMAGE BLUR CORRECTION”. In the drawing of “no image blurcorrection”, the six graphs in the left column show tangentialaberrations, and the four graphs in the right column show sagittalaberrations. In addition, in order from the top, the following areshown: an aberration at a position where the image height is 0 at thewide-angle end; aberrations at a position where the image height is 80%of the maximum image height on the negative side at the wide-angle end;aberrations at a position where the image height is 80% of the maximumimage height on the positive side at the wide-angle end; an aberrationat a position where the image height is 0 at the telephoto end;aberrations at the position where the image height is 80% of the maximumimage height on the negative side at the telephoto end; and aberrationsat a position where the image height is 80% of the maximum image heighton the positive side at the telephoto end. In the drawing, co means ahalf angle of view, and aberrations at the d line, the C line, the Fline, and the g line are indicated by the solid line, the long dashedline, the short dashed line, and the chain line, respectively. The sameapplies to the drawing “IMAGE BLUR CORRECTION”.

Symbols, meanings, description methods, and illustration methods of therespective data pieces according to Example 1 are the same as those inthe following examples unless otherwise noted. Therefore, in thefollowing description, repeated description will be omitted.

Example 2

FIG. 2 is a cross-sectional view showing a configuration of the zoomlens of Example 2. The zoom lens of Example 2 has the same configurationas the outline of the zoom lens of Example 1. Regarding the zoom lens ofExample 2, Table 4 shows basic lens data, Table 5 shows specificationand variable surface distances, Table 6 shows aspheric surfacecoefficients, and FIGS. 14 and 25 shows aberration diagrams.

TABLE 4 Example 2 Sn R D Nd νd θgF 1 131.57797 1.500 1.84699 22.650.62089 2 67.55520 5.403 1.71053 55.97 0.54269 3 425.49740 0.150 458.77808 4.988 1.71727 55.64 0.54270 5 201.80604 DD[5]  *6 416.646371.500 1.77322 44.08 0.56460 *7 13.41082 8.329 8 −17.23302 0.700 1.7021649.39 0.55742 9 −56.24107 0.710 10 105.60952 3.078 1.94595 17.98 0.6546011 −41.31604 1.393 12 −20.80363 0.700 1.84699 22.65 0.62089 13 −31.68401DD[13] 14(St) ∞ 0.500 *15 18.85186 5.206 1.68948 31.02 0.59874 *16−116.01791 2.093 17 62.51501 0.600 1.84573 22.71 0.62065 18 12.148013.609 1.58163 61.86 0.54174 19 23.68045 1.600 *20 16.74149 5.994 1.4970081.61 0.53887 *21 −21.09500 DD[21] 22 68.81562 2.112 1.85896 22.730.62844 23 −77.49432 0.610 1.80440 39.59 0.57297 24 17.95124 DD[24] *25116.14419 4.604 1.58313 59.38 0.54237 *26 −38.32872 0.150 27 −139.217601.500 1.74841 53.16 0.54494 28 34.13398 4.468 1.48749 70.24 0.53007 29−517.25402 12.405  30 ∞ 2.850 1.51680 64.20 0.53430 31 ∞ 1.000

TABLE 5 Example 2 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.499 36.538 77.761 FNo. 4.12 4.13 4.13 2ω(°) 87.0 41.0 20.0DD[5] 0.800 14.215 35.151 DD[13] 19.731 6.650 2.034 DD[21] 2.499 4.3143.105 DD[24] 4.241 17.050 31.033

TABLE 6 Example 2 Sn 6 7 15 16 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −1.4966116E−05  −4.8836895E−05  −2.2251192E−05 −8.4475879E−07  A5 2.4803547E−06 3.1121405E−06 6.3217095E−067.2024578E−06 A6 1.0988494E−07 1.3659886E−07 −1.6604772E−06 −2.0575753E−06  A7 −1.3252893E−08  −4.1764770E−08  1.4695868E−072.0514768E−07 A8 −1.5742775E−10  2.8763475E−09 4.4767350E−095.4178092E−09 A9 2.7322906E−11 1.8816394E−10 −1.3614374E−09 −2.2676798E−09  A10 −1.9198265E−13  −1.8097317E−11  3.9609326E−119.1845861E−11 Sn 20 21 25 26 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −4.5120903E−05  3.1124682E−05 1.3940193E−053.7240038E−05 A5 −1.5053854E−05  −1.0787545E−05  1.8917020E−06−3.0716491E−06  A6 9.0451192E−06 6.7602758E−06 −7.5934360E−08 2.0095116E−07 A7 −2.6021055E−06  −1.8891461E−06  1.1141342E−083.8494441E−08 A8 3.9769025E−07 2.7813451E−07 −1.1552052E−09 −4.0348499E−09  A9 −3.1214244E−08  −2.1199576E−08  −5.8037554E−11 −7.9733250E−11  A10 9.7019543E−10 6.4468762E−10 7.6219560E−121.3365832E−11

Example 3

FIG. 3 is a cross-sectional view showing a configuration of the zoomlens of Example 3. The zoom lens of Example 3 has the same configurationas the outline of the zoom lens of Example 1. Regarding the zoom lens ofExample 3, Table 7 shows basic lens data, Table 8 shows specificationand variable surface distances, Table 9 shows aspheric surfacecoefficients, and FIGS. 15 and 26 shows aberration diagrams.

TABLE 7 Example 3 Sn R D Nd νd θgF 1 127.23794 1.500 1.95906 17.470.65993 2 68.36118 5.188 1.88300 40.76 0.56679 3 353.42458 0.150 451.05060 5.536 1.61014 60.76 0.54217 5 176.82084 DD[5]  *6 197.670801.500 1.83268 39.67 0.57242 *7 12.65278 8.030 8 −16.65132 0.700 1.7005456.20 0.54325 9 −64.65678 0.526 10 88.26127 3.078 1.94595 17.98 0.6546011 −40.30466 1.695 12 −18.46617 0.700 1.79664 25.42 0.61156 13 −29.44876DD[13] 14(St) ∞ 0.500 *15 19.22635 6.000 1.68948 31.02 0.59874 *16−52.94274 1.415 17 66.22177 0.600 1.84693 22.65 0.62088 18 11.655035.166 1.51822 64.30 0.53826 19 47.46314 1.600 *20 17.59201 6.000 1.41390100.82 0.53373 *21 −21.14694 DD[21] 22 61.73120 2.000 1.95906 17.470.65993 23 −178.94136 0.610 1.80440 39.59 0.57297 24 16.61010 DD[24] *25202.68635 4.726 1.58313 59.38 0.54237 *26 −31.31369 0.877 27 −104.688381.500 1.85883 30.00 0.59793 28 32.17344 4.796 1.59827 46.77 0.56598 29−259.27698 9.888 30 ∞ 2.850 1.51680 64.20 0.53430 31 ∞ 1.000

TABLE 8 Example 3 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.489 36.516 77.714 FNo. 4.13 4.13 4.13 2ω(°) 86.2 40.8 20.0DD[5] 0.800 12.911 31.637 DD[13] 17.932 7.217 2.961 DD[21] 2.496 3.9823.292 DD[24] 5.645 20.110 33.038

TABLE 9 Example 3 Sn 6 7 15 16 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −1.7395978E−05  −5.3566161E−05  −2.7226806E−05 1.0020418E−06 A5 2.4371987E−06 3.5906409E−06 6.4928718E−06 7.3657138E−06A6 1.0344411E−07 3.6976701E−08 −1.6697118E−06  −2.0833633E−06  A7−1.2677658E−08  −4.6667222E−08  1.4480647E−07 2.0462468E−07 A8−1.3209070E−10  2.5670020E−09 4.5420622E−09 5.1012960E−09 A92.7741079E−11 4.6681502E−10 −1.3619176E−09  −2.2513360E−09  A10−3.0574453E−13  −3.5875113E−11  4.0475784E−11 9.4398056E−11 Sn 20 21 2526 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A30.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 A4−3.0824782E−05  3.9383615E−05 1.8948283E−05 4.9627909E−05 A5−1.5396547E−05  −1.2125492E−05  2.1106325E−06 −3.1509149E−06  A68.9851464E−06 6.7627679E−06 −7.6404143E−08  2.0026483E−07 A7−2.6039940E−06  −1.8805572E−06  1.2442486E−08 3.8679839E−08 A83.9904814E−07 2.7760299E−07 −1.2366207E−09  −3.9954683E−09  A9−3.1272708E−08  −2.1241901E−08  −5.9605050E−11  −7.8251033E−11  A109.4962207E−10 6.2918187E−10 7.8724492E−12 1.3297708E−11

Example 4

FIG. 4 is a cross-sectional view showing a configuration of the zoomlens of Example 4. The zoom lens of Example 4 has the same configurationas the outline of the zoom lens of Example 1. Regarding the zoom lens ofExample 4, Table 10 shows basic lens data, Table 11 shows specificationand variable surface distances, Table 12 shows aspheric surfacecoefficients, and FIGS. 16 and 27 shows aberration diagrams.

TABLE 10 Example 4 Sn R D Nd νd θgF 1 140.15920 1.500 1.92286 18.900.64960 2 76.57562 4.600 1.77250 49.60 0.55212 3 338.17154 0.150 461.25862 4.716 1.77423 47.35 0.55640 5 190.24297 DD[5]  *6 416.651531.500 1.80998 40.95 0.56644 *7 14.54810 8.214 8 −19.31908 0.700 1.6743937.17 0.58327 9 −115.85599 0.150 10 98.21866 4.473 1.94595 17.98 0.6546011 −36.04825 1.330 12 −21.47670 0.700 1.83667 23.17 0.61902 13 −30.19670DD[13] 14(St) ∞ 0.500 *15 16.81445 5.001 1.68948 31.02 0.59874 *16−245.46598 0.174 17 34.32449 0.700 1.85896 22.73 0.62844 18 11.107363.010 1.61800 63.33 0.54414 19 16.22876 1.600 *20 17.65941 5.267 1.4970081.61 0.53887 *21 −22.39316 DD[21] 22 130.93020 2.000 1.84666 23.780.62054 23 −90.34011 0.610 1.80440 39.59 0.57297 24 18.86350 DD[24] 25120.70098 3.000 1.77357 50.62 0.54837 26 −99.45133 1.310 1.76574 43.540.56641 27 123.89655 0.974 *28 −101.34788 3.778 1.58313 59.38 0.54237*29 −27.87020 14.622  30 ∞ 2.850 1.51680 64.20 0.53430 31 ∞ 1.000

TABLE 11 Example 4 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.529 36.603 77.900 FNo. 4.12 4.12 4.12 2ω(°) 85.0 40.6 19.6DD[5] 0.800 12.423 37.532 DD[13] 22.958 6.937 1.196 DD[21] 2.498 3.9503.020 DD[24] 3.826 18.352 28.365

TABLE 12 Example 4 Sn 6 7 15 16 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −2.1573661E−05  −3.9022740E−05  −4.8405706E−05 −4.4169435E−05  A5 3.4921030E−06 1.1943667E−06 8.8946671E−061.5305559E−05 A6 8.2025268E−08 4.2655315E−07 −2.1312271E−06 −3.5539537E−06  A7 −1.5931433E−08  −3.3045461E−08  9.2082608E−082.3009141E−07 A8 −3.1506580E−11  4.3607644E−10 1.3166819E−081.4786052E−08 A9 3.3946573E−11 1.1452099E−10 −1.3579324E−09 −3.5116072E−09  A10 −6.0576814E−13  −3.0153512E−12  −4.2184579E−11 1.2094256E−10 Sn 20 21 28 29 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −5.2874727E−05  2.3466953E−05 −4.1957056E−06 2.5963740E−05 A5 −7.3734243E−06  −8.3472818E−06  4.6862198E−06−1.8441578E−06  A6 8.6426532E−06 7.1763170E−06 −4.8423437E−07 1.9590948E−07 A7 −2.6160163E−06  −1.9596690E−06  1.4614956E−082.5074796E−09 A8 3.9003698E−07 2.7207633E−07 2.0827550E−09−1.3312155E−09  A9 −3.0978989E−08  −2.0482438E−08  −1.8838102E−10 8.4706074E−11 A10 1.0991537E−09 7.1873611E−10 5.3234032E−12−9.1069571E−13 

Example 5

FIG. 5 is a cross-sectional view showing a configuration of the zoomlens of Example 5. The zoom lens of Example 5 has the same configurationas the outline of the zoom lens of Example 1. Regarding the zoom lens ofExample 5, Table 13 shows basic lens data, Table 14 shows specificationand variable surface distances, Table 15 shows aspheric surfacecoefficients, and FIGS. 17 and 28 shows aberration diagrams.

TABLE 13 Example 5 Sn R D Nd νd θgF 1 276.64953 1.500 2.10420 17.020.66311 2 106.19860 4.552 1.89190 37.13 0.57813 3 −1677.82377 0.150 456.33140 4.817 1.77250 49.60 0.55212 5 155.87618 DD[5]  *6 149.553161.500 1.80998 40.95 0.56644 *7 13.57868 8.395 8 −17.68901 0.700 1.7030052.38 0.55070 9 −54.91943 0.875 10 105.03887 3.591 1.94595 17.98 0.6546011 −46.32614 1.558 12 −20.64389 0.700 1.78880 28.43 0.60092 13 −30.18069DD[13] 14(St) ∞ 0.500 *15 19.33407 5.075 1.68948 31.02 0.59874 *16−182.20393 1.728 17 41.69835 0.700 1.77830 23.91 0.62490 18 10.658944.233 1.59410 60.47 0.55516 19 20.25219 1.600 *20 16.23382 6.000 1.4387594.66 0.53402 *21 −20.10236 DD[21] 22 77.20179 2.000 1.85896 22.730.62844 23 −120.80822 0.610 1.80440 39.59 0.57297 24 19.96950 DD[24] 25198.83439 3.010 1.95375 32.32 0.59056 26 −77.70704 1.300 2.00100 29.140.59974 27 173.84906 1.124 *28 −63.29840 3.294 1.58313 59.38 0.54237 *29−27.70698 14.724  30 ∞ 2.850 1.51680 64.20 0.53430 31 ∞ 1.000

TABLE 14 Example 5 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.494 36.526 77.736 FNo. 4.12 4.13 4.13 2ω(°) 86.6 40.8 19.8DD[5] 0.800 12.774 34.757 DD[13] 19.916 6.256 1.433 DD[21] 2.494 3.9342.492 DD[24] 3.953 18.598 32.685

TABLE 15 Example 5 Sn 6 7 15 16 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −2.3655363E−05  −5.3728186E−05  −3.4165966E−05 −2.5732809E−05  A5 2.8434972E−06 3.8702629E−06 9.0520891E−061.4563115E−05 A6 1.2915494E−07 −1.1307658E−07  −1.7407849E−06 −3.3956346E−06  A7 −1.5994964E−08  −1.5080856E−08  6.7458682E−082.5664612E−07 A8 −1.1375601E−10  3.5036777E−09 1.2063751E−081.4397885E−08 A9 2.9945832E−11 −1.2107170E−10  −1.1489145E−09 −3.3702215E−09  A10 −1.9862184E−13  −6.5028915E−12  −6.5171513E−12 1.1861303E−10 Sn 20 21 28 29 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −4.4280271E−05  4.4114101E−05 9.3389749E−064.0215836E−05 A5 −1.5653598E−05  −1.5431545E−05  6.7261449E−06−8.4851556E−07  A6 9.0540750E−06 7.7459060E−06 −6.0563648E−07 1.9487091E−07 A7 −2.5669171E−06  −1.9405480E−06  1.1966300E−08−3.1052206E−10  A8 3.9472318E−07 2.7266272E−07 1.6794483E−09−1.8555477E−09  A9 −3.1668403E−08  −2.0784346E−08  −1.5723829E−10 8.6125504E−11 A10 1.0098062E−09 6.4383577E−10 4.7559789E−12−1.2615438E−13 

Example 6

FIG. 6 is a cross-sectional view showing a configuration of the zoomlens of Example 6. In the zoom lens of Example 6, the second lens groupG2 consists of three lenses L21 to L23 in order from the object side tothe image side, and the fifth lens group G5 consists of one lens L51.Except for the points described above, the zoom lens has substantiallythe same configuration as that of the zoom lens of Example 1. Regardingthe zoom lens of Example 6, Table 16 shows basic lens data, Table 17shows specification and variable surface distances, Table 18 showsaspheric surface coefficients, and FIGS. 18 and 29 shows aberrationdiagrams.

TABLE 16 Sn R D Nd νd θgF 1 195.53115 1.500 1.85896 22.73 0.62844 286.76544 5.023 1.72720 55.14 0.54272 3 1574.16747 0.150 4 59.25939 4.7891.74873 53.13 0.54497 5 176.68922 DD[5]  6 95.14642 0.900 1.73147 54.850.54289 7 11.67452 8.554 *8 −22.02773 1.500 1.69350 53.20 0.54661 *9−73.73379 0.863 10 181.48116 2.290 1.95906 17.47 0.65993 11 −90.14539DD[11] 12(St) ∞ 0.500 *13 18.98763 5.806 1.68948 31.02 0.59874 *14−103.40755 0.150 15 46.67854 0.600 1.84700 22.65 0.62089 16 12.354522.337 1.59597 60.18 0.54388 17 16.67564 1.600 *18 16.37080 5.591 1.4970081.61 0.53887 *19 −18.28048 DD[19] 20 115.11383 2.111 1.89286 20.360.63944 21 −72.73789 0.610 1.73800 32.33 0.59005 22 17.38170 DD[22] *23−194.24953 5.000 1.58313 59.38 0.54237 *24 −35.49614 15.307  25 ∞ 2.8501.51680 64.20 0.53430 26 ∞ 1.000

TABLE 17 Example 6 Wide-angle Telephoto end Middle end Zr 1.000 2.0684.124 f 16.494 34.108 68.018 FNo. 4.12 4.12 4.12 2ω(°) 86.8 43.4 22.8DD[5] 0.800 15.581 36.540 DD[11] 19.977 6.249 1.786 DD[19] 2.498 4.6823.255 DD[22] 7.702 15.844 28.468

TABLE 18 Example 6 Sn 8 9 13 14 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 4.7373189E−05 2.5192973E−05 −6.3293482E−05 −5.7886884E−05  A5 −9.6054676E−06  −1.0829721E−05  6.7008866E−061.9094374E−06 A6 −4.9995523E−07  −2.8512812E−07  −2.2724721E−06 −1.6043189E−06  A7 1.8214891E−07 1.8202868E−07 1.5488404E−072.4076072E−07 A8 −8.7603437E−09  −9.8345504E−09  1.0364797E−08−8.6072636E−09  A9 −1.0127774E−09  −1.0026794E−09  −2.2613856E−09 −2.7327284E−09  A10 6.8101188E−11 7.7857893E−11 4.1839797E−121.7631883E−10 Sn 18 19 23 24 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −5.6626742E−05  2.3149554E−05 −2.4360205E−05 −7.3443391E−06  A5 −1.7898609E−05  −3.4762525E−06  4.8569381E−06−9.4393343E−07  A6 9.0631618E−06 5.4719541E−06 −1.8355027E−07 4.6339658E−07 A7 −2.5725642E−06  −1.9400684E−06  −6.6976288E−09 −2.2416225E−08  A8 4.0370075E−07 3.0286510E−07 9.8021940E−10−1.6054852E−09  A9 −3.1983972E−08  −2.1697419E−08  −4.8407130E−11 1.6800329E−10 A10 8.8530237E−10 4.7630221E−10 1.0659909E−12−3.9963385E−12 

Example 7

FIG. 7 is a cross-sectional view showing a configuration of the zoomlens of Example 7. In the zoom lens of Example 7, the fifth lens groupG5 consists of one lens L51, and all the lens groups including the fifthlens group G5 move along the optical axis Z by changing all thedistances in the direction of the optical axis of lens groups adjacentto each other during zooming. Except for the points described above, thezoom lens has substantially the same configuration as that of the zoomlens of Example 1. Regarding the zoom lens of Example 7, Table 19 showsbasic lens data, Table 20 shows specification and variable surfacedistances, Table 21 shows aspheric surface coefficients, and FIGS. 19and 30 shows aberration diagrams.

TABLE 19 Example 7 Sn R D Nd νd θgF 1 113.64101 1.500 1.84666 23.780.62054 2 58.14689 4.447 1.71345 55.83 0.54270 3 211.06714 0.150 451.16998 4.623 1.75865 52.14 0.54625 5 183.59726 DD[5] *6 416.729171.500 1.80139 45.45 0.55814 *7 12.09655 5.782 8 −29.29465 0.710 1.8470143.30 0.56102 9 416.72918 3.417 1.87068 21.47 0.62537 10 −22.00226 0.936*11 −24.17670 1.200 1.83135 33.60 0.58952 *12 −47.50496 DD[12] 13(St) ∞0.500 *14 17.67089 5.666 1.68948 31.02 0.59874 *15 −46.67564 0.150 1677.29506 0.600 1.84700 22.65 0.62089 17 12.52123 2.313 1.54544 63.250.54027 18 17.13631 1.600 *19 16.87557 5.634 1.49700 81.61 0.53887 *20−17.56029 DD[20] 21 233.79674 1.952 1.89286 20.36 0.63944 22 −55.178460.610 1.73800 32.33 0.59005 23 18.48020 DD[23] 24 −92.29233 4.7221.68005 57.50 0.54262 25 −31.83840 DD[25] 26 ∞ 2.850 1.51680 64.200.53430 27 ∞ 1.000

TABLE 20 Example 7 Wide-angle Telephoto end Middle end Zr 1.000 2.0684.124 f 16.500 34.120 68.042 FNo. 4.12 4.12 4.12 2ω(°) 85.8 43.4 22.8DD[5] 0.800 15.662 30.734 DD[12] 17.213 6.756 1.182 DD[20] 2.497 4.1022.872 DD[23] 6.364 15.608 26.540 DD[25] 16.346 15.900 20.967

TABLE 21 Example 7 Sn 6 7 11 12 KA 1.0000000E+00  1.0000000E+00 1.0000000E+00 1.0000000E+00 A3 0.0000000E+00  0.0000000E+00 0.0000000E+00 0.0000000E+00 A4 1.8091328E−05 −1.2314959E−05−2.5016662E−04 −2.4329153E−04  A5 5.1803351E−06  1.5867207E−05−5.0108301E−06 −4.8645063E−06  A6 −1.9803780E−07  −1.0912822E−06 3.7868352E−06 3.6275866E−06 A7 −3.7487095E−08  −2.6542143E−08−2.8809156E−08 −2.4969052E−08  A8 1.2484754E−09  1.7170655E−08−2.7839049E−08 −3.0653783E−08  A9 9.2233607E−11 −8.6841684E−11−6.3320407E−11 4.3472503E−11 A10 −3.3072791E−12  −6.4486092E−11 5.4737239E−11 9.5255312E−11 Sn 14 15 19 20 KA  1.0000000E+001.0000000E+00 1.0000000E+00 1.0000000E+00 A3  0.0000000E+000.0000000E+00 0.0000000E+00 0.0000000E+00 A4 −8.0910133E−05−5.5923151E−05  −6.0529074E−05  2.8994012E−05 A5  1.0582953E−051.0415673E−05 −1.2842890E−05  −2.9594968E−06  A6 −2.2364914E−06−3.5019710E−06  8.0452982E−06 5.2756847E−06 A7 −6.6409847E−083.2795082E−07 −2.4875696E−06  −1.9390444E−06  A8  3.4546021E−084.0349678E−09 4.0134090E−07 3.0612004E−07 A9 −1.2577609E−09−4.4216452E−09  −3.2658987E−08  −2.1920891E−08  A10 −2.3812027E−102.0147480E−10 9.8120085E−10 4.9326041E−10

Example 8

FIG. 8 is a cross-sectional view showing a configuration of the zoomlens of Example 8. In the zoom lens of Example 8, the fifth lens groupG5 consists of one lens L51, and all the lens groups including the fifthlens group G5 move along the optical axis Z by changing all thedistances in the direction of the optical axis of lens groups adjacentto each other during zooming. Except for the points described above, thezoom lens has substantially the same configuration as that of the zoomlens of Example 1. Regarding the zoom lens of Example 8, Table 22 showsbasic lens data, Table 23 shows specification and variable surfacedistances, Table 24 shows aspheric surface coefficients, and FIGS. 20and 31 shows aberration diagrams.

TABLE 22 Example 8 Sn R D Nd νd θgF 1 116.96901 1.500 1.84666 23.780.62054 2 62.11394 4.708 1.65474 58.76 0.54248 3 393.92446 0.150 450.08602 4.780 1.68308 57.35 0.54263 5 195.33798 DD[5] *6 416.666451.500 1.80139 45.45 0.55814 *7 11.69322 6.093 8 −31.71325 0.700 1.7887749.12 0.55057 9 57.59597 4.182 1.78199 25.90 0.60989 10 −21.59297 0.613*11 −27.18976 1.200 1.85135 40.10 0.56954 *12 −55.92124 DD[12] 13(St) ∞0.500 *14 15.27381 5.029 1.68948 31.02 0.59874 *15 −58.57788 0.710 16135.18908 0.600 1.79459 25.27 0.61188 17 9.93672 2.231 1.53610 63.610.53967 18 16.62362 1.600 *19 14.45534 4.452 1.49700 81.61 0.53887 *20−17.34341 DD[20] 21 1369.27629 1.999 1.89286 20.36 0.63944 22 −36.544130.610 1.73800 32.33 0.59005 23 17.08005 DD[23] 24 −96.75442 4.8831.51599 53.22 0.55385 25 −28.74283 DD[25] 26 ∞ 2.850 1.51680 64.200.53430 27 ∞ 1.000

TABLE 23 Example 8 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.495 36.528 77.740 FNo. 3.61 4.79 5.72 2ω(°) 86.4 41.2 20.2DD[5] 0.800 12.570 32.398 DD[12] 19.269 5.515 1.182 DD[20] 2.498 4.6633.260 DD[23] 7.924 17.849 29.971 DD[25] 14.660 15.418 17.415

TABLE 24 Example 8 Sn 6 7 11 12 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −5.3370017E−05  −9.2240206E−05  −2.1397479E−04 −2.0580119E−04  A5 1.2857344E−05 2.4601542E−05 −4.8937900E−06 −7.8781394E−06  A6 2.7493740E−09 −1.0854913E−06  3.2921030E−063.5195188E−06 A7 −9.9469272E−08  −1.2258560E−07  9.0515517E−095.6459044E−08 A8 2.5543665E−09 2.5391244E−08 −2.1559518E−08 −3.4837612E−08  A9 2.4298503E−10 3.1239151E−10 −4.2937320E−10 −5.6547589E−10  A10 −9.4647334E−12  −1.1498912E−10  1.1400081E−111.2284443E−10 Sn 14 15 19 20 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −5.8998224E−05  −4.3126794E−05  −1.0850211E−04 1.1213377E−05 A5 8.9478792E−07 3.1985514E−06 2.2247176E−06 1.0635823E−05A6 −1.1123416E−06  −2.4298590E−06  6.0320674E−06 3.6812248E−06 A74.0793820E−08 3.6302388E−07 −2.5907002E−06  −2.0738128E−06  A81.0171003E−08 −1.9800330E−08  4.3938268E−07 3.4144147E−07 A9−2.3885984E−09  −4.7031909E−09  −3.2513951E−08  −2.1331256E−08  A10−1.2813731E−10  3.1586098E−10 7.8340797E−10 2.8684695E−10

Example 9

FIG. 9 is a cross-sectional view showing a configuration of the zoomlens of Example 9. In the zoom lens of Example 9, the fifth lens groupG5 consists of one lens L51, and all the lens groups including the fifthlens group G5 move along the optical axis Z by changing all thedistances in the direction of the optical axis of lens groups adjacentto each other during zooming. Except for the points described above, thezoom lens has substantially the same configuration as that of the zoomlens of Example 1. Regarding the zoom lens of Example 9, Table 25 showsbasic lens data, Table 26 shows specification and variable surfacedistances, Table 27 shows aspheric surface coefficients, and FIGS. 21and 32 shows aberration diagrams.

TABLE 25 Example 9 Sn R D Nd νd θgF 1 63.32268 1.500 1.84666 23.780.62054 2 39.15094 5.253 1.73001 51.57 0.55042 3 96.46578 0.150 442.55067 4.863 1.78112 49.89 0.54941 5 132.53932 DD[5] *6 416.729181.500 1.80139 45.45 0.55814 *7 10.83401 6.151 8 −37.04296 0.710 1.8470043.30 0.56102 9 416.72918 3.122 1.86858 21.57 0.62497 10 −25.51502 0.550*11 −33.55142 1.200 1.84701 43.30 0.56102 *12 −85.47266 DD[12] 13(St) ∞0.500 *14 18.30004 4.910 1.68948 31.02 0.59874 *15 −60.60573 0.150 1668.05349 0.600 1.84064 23.16 0.61917 17 12.81549 2.135 1.52740 52.310.55580 18 17.34604 1.600 *19 17.58352 5.629 1.49700 81.61 0.53887 *20−16.81802 DD[20] 21 216.54557 1.882 1.85896 22.73 0.62844 22 −59.498320.610 1.73800 32.33 0.59005 23 19.04753 DD[23] 24 −112.34760 4.0081.67878 53.85 0.55001 25 −30.30405 DD[25] 26 ∞ 2.850 1.51680 64.200.53430 27 ∞ 1.000

TABLE 26 Example 9 Wide-angle Telephoto end Middle end Zr 1.000 2.0684.124 f 16.524 34.170 68.141 FNo. 4.12 4.12 4.12 2ω(°) 84.8 43.8 23.0DD[5] 0.800 12.584 23.745 DD[12] 17.648 8.336 1.165 DD[20] 3.540 4.4683.155 DD[23] 6.481 17.463 24.384 DD[25] 16.802 16.887 26.509

TABLE 27 Example 9 Sn 6 7 11 12 KA 1.0000000E+00  1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00  0.0000000E+000.0000000E+00 0.0000000E+00 A4 1.2483959E−05 −2.1822112E−05−2.4682274E−04  −2.4670708E−04  A5 5.1148046E−06  1.2567627E−05−5.2400186E−06  −5.6908412E−06  A6 −1.7791453E−07  −4.9607841E−073.9026046E−06 3.7077117E−06 A7 −3.8805889E−08  −1.4624386E−08−9.7211739E−09  1.3124815E−11 A8 1.5642458E−09  1.1750599E−08−2.8850749E−08  −3.1460097E−08  A9 7.1751179E−11 −1.7414577E−101.3812847E−11 4.0932415E−11 A10 −3.3762849E−12  −1.0037514E−116.7087029E−11 8.9012201E−11 Sn 14 15 19 20 KA  1.0000000E+001.0000000E+00 1.0000000E+00 1.0000000E+00 A3  0.0000000E+000.0000000E+00 0.0000000E+00 0.0000000E+00 A4 −8.6565866E−05−8.0561004E−05  −7.6341409E−05  1.0148045E−05 A5  9.8877771E−061.2318453E−05 −1.3773755E−05  1.0168377E−07 A6 −2.1362462E−06−3.7643994E−06  8.4739468E−06 4.9693136E−06 A7 −8.2316639E−083.1662448E−07 −2.5212635E−06  −1.9345842E−06  A8  3.3253841E−085.3583168E−09 3.9874662E−07 3.0330134E−07 A9 −1.3565995E−09−4.4399578E−09  −3.2945861E−08  −2.2069840E−08  A10 −2.3862198E−101.9520412E−10 9.7946305E−10 4.8729525E−10

Example 10

FIG. 10 is a cross-sectional view showing a configuration of the zoomlens of Example 10. In the zoom lens of Example 10, the fifth lens groupG5 consists of one lens L51, and all the lens groups including the fifthlens group G5 move along the optical axis Z by changing all thedistances in the direction of the optical axis of lens groups adjacentto each other during zooming. Except for the points described above, thezoom lens has substantially the same configuration as that of the zoomlens of Example 1. Regarding the zoom lens of Example 10, Table 28 showsbasic lens data, Table 29 shows specification and variable surfacedistances, Table 30 shows aspheric surface coefficients, and FIGS. 22and 33 shows aberration diagrams.

TABLE 28 Example 10 Sn R D Nd νd θgF 1 110.51724 1.500 1.84666 23.780.62054 2 55.36877 5.023 1.64850 53.02 0.55487 3 315.13587 0.150 453.12546 4.604 1.72818 52.65 0.54819 5 223.06908 DD[5] *6 416.614821.500 1.80139 45.45 0.55814 *7 12.08307 5.872 8 −31.48789 0.700 1.7992148.08 0.55222 9 67.98488 4.020 1.79300 25.35 0.61163 10 −21.48315 0.651*11 −24.95184 1.200 1.85135 40.10 0.56954 *12 −53.43944 DD[12] 13(St) ∞0.500 *14 15.38319 4.983 1.68948 31.02 0.59874 *15 −56.10848 0.854 16193.00748 0.600 1.81718 25.31 0.61244 17 10.21793 2.123 1.53291 63.710.53949 18 16.53024 1.768 *19 14.54004 4.814 1.53775 74.70 0.53936 *20−17.19165 DD[20] 21 −893.74776 2.227 1.89286 20.36 0.63944 22 −33.660600.610 1.73800 32.33 0.59005 23 16.84692 DD[23] 24 −76.65356 4.3901.51600 59.57 0.54486 25 −26.95790 DD[25] 26 ∞ 2.850 1.51680 64.200.53430 27 ∞ 1.000

TABLE 29 Example 10 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.503 36.546 77.777 FNo. 3.61 4.84 5.77 2ω(°) 87.0 41.4 20.2DD[5] 0.800 12.167 32.605 DD[12] 19.040 5.621 1.169 DD[20] 2.499 4.5213.573 DD[23] 8.190 19.285 30.369 DD[25] 14.585 14.988 16.619

TABLE 30 Example 10 Sn 6 7 11 12 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −5.0917286E−05  −8.8075470E−05  −2.1379959E−04 −2.0413890E−04  A5 1.2781851E−05 2.4829902E−05 −5.0991835E−06 −7.8919736E−06  A6 −3.2468558E−09  −1.1836899E−06  3.3263984E−063.5371433E−06 A7 −9.9764766E−08  −1.0715768E−07  1.9812913E−085.5232556E−08 A8 2.5347225E−09 2.4607403E−08 −2.2830503E−08 −3.4472923E−08  A9 2.4339282E−10 2.5218920E−10 −4.3353828E−10 −5.6005695E−10  A10 −9.2161232E−12  −1.1775357E−10  1.1269996E−111.2018373E−10 Sn 14 15 19 20 KA  1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3  0.0000000E+00 0.0000000E+000.0000000E+00 0.0000000E+00 A4 −5.6765193E−05 −4.4655190E−05 −1.0074194E−04  2.4509451E−05 A5 −1.3128489E−06 4.8343020E−07−5.3553740E−08  7.1248534E−06 A6 −1.0972584E−06 −2.4736241E−06 5.6518125E−06 3.5612444E−06 A7  2.8407847E−08 3.5501580E−07−2.5162466E−06  −2.0291991E−06  A8  1.0487077E−08 −1.9909438E−08 4.3729982E−07 3.4086074E−07 A9 −2.7278899E−09 −4.5520823E−09 −3.2450348E−08  −2.1485957E−08  A10 −1.2685596E−10 3.1668339E−107.6894063E−10 2.8683412E−10

Example 11

FIG. 11 is a cross-sectional view showing a configuration of the zoomlens of Example 11. The zoom lens of Example 11 has the sameconfiguration as the outline of the zoom lens of Example 1. Regardingthe zoom lens of Example 11, Table 31 shows basic lens data, Table 32shows specification and variable surface distances, Table 33 showsaspheric surface coefficients, and FIGS. 23 and 34 shows aberrationdiagrams.

TABLE 31 Example 11 Sn R D Nd νd θgF 1 128.24623 1.500 1.84666 23.780.62054 2 66.35400 5.420 1.72916 54.67 0.54503 3 370.23098 0.150 460.85319 4.910 1.69680 55.53 0.54404 5 218.25042 DD[5] *6 294.105622.000 1.80780 40.89 0.56949 *7 13.29231 8.380 8 −17.12196 0.700 1.6180063.39 0.54015 9 −108.18599 0.150 10 89.95607 3.620 1.92287 20.88 0.6394311 −33.23372 1.450 12 −19.01017 0.700 1.84667 23.79 0.61771 13 −27.63008DD[13] 14(St) ∞ 1.100 *15 16.62717 4.510 1.68893 31.16 0.60397 *16−416.39974 1.640 17 50.66171 0.700 1.84667 23.79 0.61771 18 10.881003.750 1.61800 63.39 0.54015 19 19.23257 1.600 *20 16.53927 5.890 1.4971081.56 0.53859 *21 −20.80043 DD[21] 22 87.20800 2.000 1.85896 22.730.62844 23 −87.20800 0.610 1.80440 39.59 0.57297 24 20.15648 DD[24] 25398.56925 3.300 1.51680 64.20 0.53430 26 −46.61600 1.200 1.69350 53.350.54844 27 ∞ 0.511 *28 −83.44813 3.690 1.58313 59.46 0.54067 *29−29.56019 14.614  30 ∞ 2.850 1.51680 64.20 0.53430 31 ∞ 1.000

TABLE 32 Example 11 Wide-angle Telephoto end Middle end Zr 1.000 2.2154.713 f 16.497 36.533 77.751 FNo. 4.12 4.12 4.13 2ω(°) 87.2 40.4 19.8DD[5] 0.800 16.301 36.160 DD[13] 20.010 6.315 0.948 DD[21] 2.400 3.9742.502 DD[24] 4.010 15.227 30.211

TABLE 33 Example 11 Sn 6 7 15 16 KA 1.0000000E+00 1.0000000E+001.0000000E+00 1.0000000E+00 A3 0.0000000E+00 0.0000000E+00 0.0000000E+000.0000000E+00 A4 −2.8490089E−05  −7.0282771E−05  −2.6026370E−05 −5.2519720E−06  A5 3.4001978E−06 5.3460017E−06 8.9327675E−061.1905465E−05 A6 8.6025369E−08 −3.5251621E−08  −2.0288251E−06 −2.8991687E−06  A7 −1.5881372E−08  −6.1941991E−08  1.4984851E−072.5206330E−07 A8 4.6954316E−11 6.3478737E−09 8.9124018E−09 1.1490979E−08A9 2.5563829E−11 4.1329015E−11 −1.6175571E−09  −3.0037271E−09  A10−2.8828379E−13  −2.5970681E−11  3.8219433E−11 1.0930036E−10 Sn 20 21 2829 KA 1.0000000E+00 1.0000000E+00 1.0000000E+00 1.0000000E+00 A30.0000000E+00 0.0000000E+00 0.0000000E+00 0.0000000E+00 A4−5.1646523E−05  3.0888509E−05 2.2349857E−05 4.5879069E−05 A5−1.3212713E−05  −1.1362506E−05  5.5598856E−06 −1.7722904E−06  A69.0512974E−06 7.4686715E−06 −8.5821407E−07  2.7031166E−07 A7−2.6426652E−06  −2.0164295E−06  1.4544149E−08 −3.9980318E−08  A83.9970349E−07 2.7982876E−07 3.8678891E−09 4.4104943E−10 A9−3.0895564E−08  −1.9958501E−08  −1.9921474E−10  2.3673571E−10 A109.5538736E−10 5.7836273E−10 −3.5162202E−14  −1.1877867E−11 

Table 34 shows values corresponding to Conditional Expressions (1) to(21) of the zoom lenses of Examples 1 to 11. In Examples 1 to 11, the dline is set as the reference wavelength. Table 34 shows the values onthe d line basis.

TABLE 34 Expression Example Example Example Example Example Examplenumber Conditional expression 1 2 3 4 5 6  (1) f1/f5 0.837 0.719 0.6211.422 0.936 1.247  (2) f4/f5 −0.342 −0.267 −0.250 −0.442 −0.381 −0.423 (3) Nd2 1.760 1.711 1.883 1.773 1.892 1.727  (4) BFw/TLw 0.168 0.1470.123 0.169 0.169 0.184  (5) f3R/f3F 0.387 0.365 0.682 0.374 0.434 0.227 (6) (1-β3Rt) × β45t 3.079 3.247 2.711 2.752 2.946 3.103  (7) vd3Rp81.61 81.61 100.82 81.61 94.66 81.61  (8) (1-β4t²) × β5t² −4.038 −4.494−4.694 −4.374 −4.084 −3.845  (9) vd4n-vd4p 16.86 16.86 22.12 15.81 16.8611.97 (10) TLw/|Y| 7.339 7.327 7.326 7.291 7.343 6.974 (11) D45t/D45w8.129 7.315 5.852 7.414 8.267 3.696 (12) BFw/(fw × tan|ωw|) 1.117 0.9790.829 0.844 1.135 1.166 (13) NdG1p 1.752 1.714 1.747 1.773 1.832 1.738(14) f2/f3 −0.771 −0.758 −0.663 −0.940 −0.773 −0.895 (15) f1/f2 −5.727−5.845 −6.204 −5.021 −5.559 −5.447 (16) f3/f4 −0.554 −0.609 −0.604−0.682 −0.572 −0.604 (17) f2/f4 0.427 0.461 0.401 0.641 0.442 0.541 (18)f3R/f3 1.020 1.003 1.247 1.075 1.058 0.975 (19) (1-β4w²) × β5w² −1.648−1.869 −1.867 −1.991 −1.620 −1.966 (20) vd1 23.78 22.65 17.47 18.9017.02 22.73 (21) vd4p 22.73 22.73 17.47 23.78 22.73 20.36 ExpressionExample Example Example Example Example number Conditional expression 78 9 10 11  (1) f1/f5 1.153 1.022 1.080 1.026 0.961  (2) f4/f5 −0.436−0.338 −0.513 −0.318 −0.370  (3) Nd2 1.713 1.655 1.730 1.649 1.729  (4)BFw/TLw 0.204 0.182 0.207 0.182 0.168  (5) f3R/f3F 0.297 0.250 0.2360.193 0.336  (6) (1-β3Rt) × β45t 3.095 3.655 3.044 4.033 3.140  (7)vd3Rp 81.61 81.61 81.61 74.70 81.56  (8) (1-β4t²) × β5t² −3.953 −5.538−3.407 −5.997 −4.069  (9) vd4n-vd4p 11.97 11.97 9.60 11.97 16.86 (10)TLw/|Y| 6.627 6.765 6.702 6.766 7.338 (11) D45t/D45w 4.170 3.782 3.7623.708 10.876 (12) BFw/(fw × tan|ωw|) 1.255 1.133 1.304 1.115 1.117 (13)NdG1p 1.736 1.669 1.756 1.688 1.713 (14) f2/f3 −0.831 −0.853 −0.743−0.856 −0.804 (15) f1/f2 −5.351 −5.313 −4.769 −5.469 −5.612 (16) f3/f4−0.594 −0.666 −0.594 −0.689 −0.575 (17) f2/f4 0.494 0.569 0.442 0.5900.462 (18) f3R/f3 1.019 0.954 1.001 0.902 0.982 (19) (1-β4w²) × β5w²−1.962 −2.553 −1.809 −2.743 −1.709

As can be seen from the above data, the zoom lenses of Examples 1 to 11each have a wide angle of view as a maximum half angle of view of 42degrees or more at the wide-angle end and a high zoom ratio as a zoomratio of 4 times or more. With such a configuration, reduction in sizeis achieved, and various aberrations are satisfactorily suppressed. As aresult, high optical performance is achieved.

Next, an imaging apparatus according to an embodiment of the presentdisclosure will be described. FIGS. 35 and 36 are external views of acamera 30 which is the imaging apparatus according to theabove-mentioned embodiment of the present disclosure. FIG. 35 is aperspective view of the camera 30 viewed from the front side, and FIG.36 is a perspective view of the camera 30 viewed from the rear side. Thecamera 30 is a so-called mirrorless type digital camera, and theinterchangeable lens 20 can be detachably attached thereto. Theinterchangeable lens 20 consists of the zoom lens 1, which is housed ina lens barrel, according to an embodiment of the present disclosure.

The camera 30 comprises a camera body 31, and a shutter button 32 and apower button 33 are provided on an upper surface of the camera body 31.Further, an operation section 34, an operation section 35, and a displaysection 36 are provided on a rear surface of the camera body 31. Thedisplay section 36 is capable of displaying a captured image and animage within an angle of view before imaging.

An imaging aperture, through which light from an imaging target isincident, is provided at the center on the front surface of the camerabody 31. A mount 37 is provided at a position corresponding to theimaging aperture. The interchangeable lens 20 is mounted on the camerabody 31 with the mount 37 interposed therebetween.

In the camera body 31, there are provided an imaging element, a signalprocessing circuit, a storage medium, and the like. The imaging elementsuch as a charge coupled device (CCD) or a complementary metal oxidesemiconductor (CMOS) outputs a captured image signal based on a subjectimage which is formed through the interchangeable lens 20. The signalprocessing circuit generates an image through processing of the capturedimage signal which is output from the imaging element. The storagemedium stores the generated image. The camera 30 is able to capture astill image or a moving image by pressing the shutter button 32, and isable to store image data, which is obtained through imaging, in thestorage medium.

The technology of the present disclosure has been hitherto describedthrough embodiments and examples, but the technology of the presentdisclosure is not limited to the above-mentioned embodiments andexamples, and may be modified into various forms. For example, valuessuch as the radius of curvature, the surface distance, the refractiveindex, the Abbe number, and the aspheric surface coefficient of eachlens are not limited to the values shown in the numerical examples, anddifferent values may be used therefor.

Further, the imaging apparatus according to the embodiment of thepresent disclosure is not limited to the above example, and may bemodified into various forms such as a camera other than the mirrorlesstype, a film camera, and a video camera.

What is claimed is:
 1. A zoom lens comprising, as lens groups, only fivelens groups consisting of, in order from an object side to an imageside: a first lens group that has a positive refractive power; a secondlens group that has a negative refractive power; a third lens group thathas a positive refractive power; a fourth lens group that has a negativerefractive power; and a fifth lens group that has a positive refractivepower, wherein an aperture stop is disposed between a lens surfaceclosest to the image side in the second lens group and a lens surfaceclosest to the object side in the fourth lens group, wherein duringzooming, by changing all distances between lens groups adjacent to eachother in a direction of an optical axis, at least the first lens group,the second lens group, the third lens group, and the fourth lens groupmove along the optical axis, wherein the first lens group consists of,in order from the object side to the image side, a first lens having anegative refractive power, a second lens having a positive refractivepower, and a third lens having a positive refractive power, whereinassuming that a focal length of the first lens group is f1, a focallength of the fifth lens group is f5, a focal length of the fourth lensgroup is f4, and a refractive index of the second lens at a d line isNd2, Conditional Expressions (1), (2), and (3) are satisfied, which arerepresented by0.4<f1/f5<2  (1),−0.7<f4/f5<−0.1  (2), and1.6<Nd2<2  (3).
 2. The zoom lens according to claim 1, wherein assumingthat a back focal length at an air conversion distance in a state wherean object at infinity is in focus at a wide-angle end is BFw, and a sumof a distance on the optical axis from a lens surface closest to theobject side to a lens surface closest to the image side and the backfocal length at the air conversion distance in the state where theobject at infinity is in focus at the wide-angle end is TLw, ConditionalExpression (4) is satisfied, which is represented by0.07<BFw/TLw<0.25  (4).
 3. The zoom lens according to claim 1, whereinthe entire third lens group or a part of the third lens group moves in adirection intersecting with the optical axis for image blur correction.4. The zoom lens according to claim 1, wherein the third lens groupconsists of, in order from the object side to the image side, a thirdlens group front group having a positive refractive power and a thirdlens group rear group having a positive refractive power, and whereinonly the third lens group rear group moves in a direction intersectingwith the optical axis for image blur correction.
 5. The zoom lensaccording to claim 4, wherein assuming that a focal length of the thirdlens group rear group is f3R, and a focal length of the third lens groupfront group is f3F, Conditional Expression (5) is satisfied, which isrepresented by0.1<f3R/f3F<0.9  (5).
 6. The zoom lens according to claim 4, whereinassuming that a lateral magnification of the third lens group rear groupin a state where the object at infinity is in focus at a telephoto endis β3Rt, and a combined lateral magnification of the fourth lens groupand the fifth lens group in the state where the object at infinity is infocus at the telephoto end is ƒ45t, Conditional Expression (6) issatisfied, which is represented by2<(1−β3Rt)×β45t<5  (6).
 7. The zoom lens according to claim 4, whereinthe third lens group rear group consists of one positive lens.
 8. Thezoom lens according to claim 4, wherein the third lens group rear grouphas at least one positive lens, and wherein assuming that an Abbe numberof the at least one positive lens in the third lens group rear groupbased on the d line is νd3Rp, Conditional Expression (7) is satisfied,which is represented by65<νd3Rp<105  (7).
 9. The zoom lens according to claim 4, wherein thethird lens group front group consists of two positive lenses and onenegative lens.
 10. The zoom lens according to claim 1, wherein only thefourth lens group moves along the optical axis during focusing from anobject at infinity to a close-range object.
 11. The zoom lens accordingto claim 10, wherein assuming that a lateral magnification of the fourthlens group in a state where the object at infinity is in focus at atelephoto end is β4t, and a lateral magnification of the fifth lensgroup in the state where the object at infinity is in focus at thetelephoto end is β5t, Conditional Expression (8) is satisfied, which isrepresented by−7<(1−β4t ²)×β5t ²<−2.6  (8).
 12. The zoom lens according to claim 1,wherein the fourth lens group consists of one positive lens and onenegative lens.
 13. The zoom lens according to claim 12, wherein assumingthat an Abbe number of the negative lens of the fourth lens group basedon the d line is νd4n, and an Abbe number of the positive lens of thefourth lens group based on the d line is νd4p, Conditional Expression(9) is satisfied, which is represented by5<νd4n−νd4p<26  (9).
 14. The zoom lens according to claim 1, whereinassuming that a sum of a distance on the optical axis from a lenssurface closest to the object side to a lens surface closest to theimage side and a back focal length at an air conversion distance in astate where the object at infinity is in focus at a wide-angle end isTLw, and a maximum image height is Y, Conditional Expression (10) issatisfied, which is represented by6<TLw/|Y|<8.6  (10).
 15. The zoom lens according to claim 1, whereinassuming that a distance on the optical axis between the fourth lensgroup and the fifth lens group in a state where an object at infinity isin focus at a telephoto end is D45t, and a distance on the optical axisbetween the fourth lens group and the fifth lens group in the statewhere the object at infinity is in focus at the wide-angle end is D45w,Conditional Expression (11) is satisfied, which is represented by2<D45t/D45w<13  (11).
 16. The zoom lens according to claim 1, whereinassuming that a back focal length at an air conversion distance in astate where an object at infinity is in focus at a wide-angle end isBFw, a focal length of the zoom lens in the state where the object atinfinity is in focus at the wide-angle end is fw, and a maximum halfangle of view in the state where the object at infinity is in focus atthe wide-angle end is ωw, Conditional Expression (12) is satisfied,which is represented by0.5<BFw/(fw×tan|ωw|)<1.6  (12).
 17. The zoom lens according to claim 1,wherein assuming that an average of the refractive index of the secondlens at the d line and a refractive index of the third lens at the dline is NdG1p, Conditional Expression (13) is satisfied, which isrepresented by1.63<NdG1p<1.9  (13).
 18. The zoom lens according to claim 1, whereinassuming that a focal length of the second lens group is f2, and a focallength of the third lens group is f3, Conditional Expression (14) issatisfied, which is represented by−1.3<f2/f3<−0.4  (14).
 19. The zoom lens according to claim 1, whereinthe fifth lens group consists of two positive lenses and one negativelens.
 20. An imaging apparatus comprising the zoom lens according toclaim 1.